DCO check workflow added to repo (#15)

### Description
DCO work flow is checked for new pull requests
Added DCO Check Workflow
Added CONTRIBUTING.md DCO Section
 
### Issues Resolved
#14 
 
### Check List
- [x] Commits are signed per the DCO using --signoff 

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check [here](https://github.com/opensearch-project/OpenSearch/blob/main/CONTRIBUTING.md#developer-certificate-of-origin).

.github/workflows/CI.yml

@@ -22,22 +22,7 @@ jobs:
       uses: actions/setup-java@v1
       with:
         java-version: ${{ matrix.java }}
-
-        # plugin-template
-    - name: Checkout AD
-      uses: actions/checkout@v2
-
-      # dependencies: OpenSearch
-    - name: Checkout OpenSearch
-      uses: actions/checkout@v2
-      with:
-        repository: 'opensearch-project/OpenSearch'
-        path: OpenSearch
-        ref: '1.0'
-    - name: Build OpenSearch
-      working-directory: ./OpenSearch
-      run: ./gradlew publishToMavenLocal -Dbuild.version_qualifier=beta1 -Dbuild.snapshot=false
 
     - name: Build and Run Tests
       run: |
-          ./gradlew build -Dopensearch.version=1.0.0-beta1
+          ./gradlew build -Dopensearch.version=1.1.0

.github/workflows/dco.yml

@@ -0,0 +1,18 @@
+name: Developer Certificate of Origin Check
+
+on: [pull_request]
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Get PR Commits
+        id: 'get-pr-commits'
+        uses: tim-actions/get-pr-commits@v1.1.0
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+      - name: DCO Check
+        uses: tim-actions/dco@v1.1.0
+        with:
+          commits: ${{ steps.get-pr-commits.outputs.commits }}

CONTRIBUTING.md

@@ -39,6 +39,52 @@ To send us a pull request, please:
 GitHub provides additional document on [forking a repository](https://help.github.com/articles/fork-a-repo/) and
 [creating a pull request](https://help.github.com/articles/creating-a-pull-request/).
 
+## Developer Certificate of Origin
+
+OpenSearch is an open source product released under the Apache 2.0 license (see either [the Apache site](https://www.apache.org/licenses/LICENSE-2.0) or the [LICENSE.txt file](LICENSE)). The Apache 2.0 license allows you to freely use, modify, distribute, and sell your own products that include Apache 2.0 licensed software.
+
+We respect intellectual property rights of others and we want to make sure all incoming contributions are correctly attributed and licensed. A Developer Certificate of Origin (DCO) is a lightweight mechanism to do that.
+
+The DCO is a declaration attached to every contribution made by every developer. In the commit message of the contribution, the developer simply adds a `Signed-off-by` statement and thereby agrees to the DCO, which you can find below or at [DeveloperCertificate.org](http://developercertificate.org/).
+
+```
+Developer's Certificate of Origin 1.1
+
+By making a contribution to this project, I certify that:
+
+(a) The contribution was created in whole or in part by me and I
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the
+    best of my knowledge, is covered under an appropriate open
+    source license and I have the right under that license to
+    submit that work with modifications, whether created in whole
+    or in part by me, under the same open source license (unless
+    I am permitted to submit under a different license), as
+    Indicated in the file; or
+
+(c) The contribution was provided directly to me by some other
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
+(d) I understand and agree that this project and the contribution
+    are public and that a record of the contribution (including
+    all personal information I submit with it, including my
+    sign-off) is maintained indefinitely and may be redistributed
+    consistent with this project or the open source license(s)
+    involved.
+ ```
+
+We require that every contribution to OpenSearch is signed with a Developer Certificate of Origin. Additionally, please use your real name. We do not accept anonymous contributors nor those utilizing pseudonyms.
+
+Each commit must include a DCO which looks like this
+
+```
+Signed-off-by: Jane Smith <jane.smith@email.com>
+```
+
+You may type this line on your own when writing your commit messages. However, if your user.name and user.email are set in your git configs, you can use `-s` or `– – signoff` to add the `Signed-off-by` line to the end of the commit message.
 
 ## Finding contributions to work on
 Looking at the existing issues is a great way to find something to contribute on. As our projects, by default, use the default GitHub issue labels (enhancement/bug/duplicate/help wanted/invalid/question/wontfix), looking at any 'help wanted' issues is a great place to start.
@@ -53,6 +99,16 @@ opensource-codeofconduct@amazon.com with any additional questions or comments.
 ## Security issue notifications
 If you discover a potential security issue in this project we ask that you notify AWS/Amazon Security via our [vulnerability reporting page](http://aws.amazon.com/security/vulnerability-reporting/). Please do **not** create a public github issue.
 
+## License Headers
+
+New files in your code contributions should contain the following license header. If you are modifying existing files with license headers, or including new files that already have license headers, do not remove or modify them without guidance.
+
+```
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+```
 
 ## Licensing
 

build.gradle

@@ -37,13 +37,15 @@ validateNebulaPom.enabled = false
 
 buildscript {
     ext {
-        opensearch_version = "1.0.0-beta1"
+        opensearch_version = "1.1.0-SNAPSHOT"
     }
 
     repositories {
+        mavenLocal()
+        maven { url "https://aws.oss.sonatype.org/content/repositories/snapshots" }
         mavenCentral()
+        maven { url "https://plugins.gradle.org/m2/" }
         jcenter()
-        mavenLocal()
     }
 
     dependencies {
@@ -53,6 +55,10 @@ buildscript {
 
 repositories {
     mavenLocal()
+    maven { url "https://aws.oss.sonatype.org/content/repositories/snapshots" }
+    mavenCentral()
+    maven { url "https://plugins.gradle.org/m2/" }
+    jcenter()
 }
 
 test {