ci: add centralized workflows for the devops-stack modules

docs: shortened comment

feat: change version on the variable file

.github/workflows/modules-linters.yaml

@@ -0,0 +1,38 @@
+---
+# GitHub Actions workflow to check that the Terraform code is well formatted and if the commits have the conventional 
+# commit message structure (the latter is needed to properly create automatic releases with Release Please).
+#
+# IMPORTANT: This workflow is called by other workflows in our DevOps Stack repositories and it is centralized here in 
+# order to be easily maintained across modules. Because of this, please make sure you're not introducing any breaking 
+# changes when modifying this workflow.
+
+name: "Linters"
+
+on:
+  workflow_call:
+
+jobs:
+  terraform-format:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: "Check out the repository"
+      uses: actions/checkout@v3
+
+    - name: Setup Terraform
+      uses: hashicorp/setup-terraform@v2
+
+    - name: "Run terraform fmt -check"
+      run: "terraform fmt -check"
+
+  commits-checks:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: "Check out the repository"
+      uses: actions/checkout@v3
+      with:
+        fetch-depth: 0 # Fetch all history for all tags and branches
+
+    - name: "Check commit messages"
+      uses: docker://aevea/commitsar

.github/workflows/modules-release-please.yaml

@@ -0,0 +1,22 @@
+---
+# GitHub Actions workflow to automatically create releases and changelogs in our DevOps Stack repositories.
+#
+# IMPORTANT: This workflow is called by other workflows in our DevOps Stack repositories and it is centralized here in 
+# order to be easily maintained across modules. Because of this, please make sure you're not introducing any breaking 
+# changes when modifying this workflow.
+
+name: "Release Modules"
+
+on:
+  workflow_call:
+
+jobs:
+  release-please:
+    runs-on: "ubuntu-latest"
+    steps:
+    - uses: "google-github-actions/release-please-action@v3"
+      with:
+        release-type: "simple"
+        bump-minor-pre-major: true
+        extra-files: |
+          variables.tf

.github/workflows/modules-terraform-docs.yaml

@@ -0,0 +1,82 @@
+---
+# GitHub Actions workflow to automatically generate documentation from the .tf files of the module.
+# The generated documentation will be injected between AsciiDoc comments on the README.adoc.
+#
+# IMPORTANT: This workflow is called by other workflows in our DevOps Stack repositories and it is centralized here in 
+# order to be easily maintained across modules. Because of this, please make sure you're not introducing any breaking 
+# changes when modifying this workflow.
+
+name: "Terraform Docs"
+
+on:
+  workflow_call:
+    inputs:
+      variants:
+        # List of the variants folders as a comma-separated list inside a string (i.e. "eks,aks,sks").
+        type: string
+        required: false
+        default: ""
+
+jobs:
+  terraform-docs:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: "Check out the repository"
+      uses: actions/checkout@v3
+      with:
+        ref: ${{ github.event.pull_request.head.ref }}
+
+    - name: "Generate Terraform docs"
+      uses: terraform-docs/gh-actions@v1.0.0
+      with:
+        working-dir: .
+        indention: 3
+        output-format: asciidoc document
+        output-file: README.adoc
+        output-method: inject
+        template: "// BEGIN_TF_DOCS\n{{ .Content }}\n// END_TF_DOCS" # Define template compatible with AsciiDoc
+        git-push: false
+
+    - name: "Generate Terraform tables"
+      uses: terraform-docs/gh-actions@v1.0.0
+      with:
+        working-dir: .
+        indention: 1 # Since the headings are not read inside the collapsible block we can indent as 1
+        output-format: asciidoc table
+        output-file: README.adoc
+        output-method: inject
+        template: "// BEGIN_TF_TABLES\n{{ .Content }}\n// END_TF_TABLES" # Define template compatible with AsciiDoc
+        args: "--hide-empty=true" # Do not show empty sections
+        git-push: false
+
+    - name: "Generate Terraform docs for the variants"
+      if: ${{ inputs.variants != '' }}
+      uses: terraform-docs/gh-actions@v1.0.0
+      with:
+        working-dir: ${{ inputs.variants }}
+        indention: 3
+        output-format: asciidoc document
+        output-file: README.adoc
+        output-method: inject
+        template: "// BEGIN_TF_DOCS\n{{ .Content }}\n// END_TF_DOCS" # Define template compatible with AsciiDoc
+        git-push: false
+
+    - name: "Generate Terraform tables for the variants"
+      if: ${{ inputs.variants != '' }}
+      uses: terraform-docs/gh-actions@v1.0.0
+      with:
+        working-dir: ${{ inputs.variants }}
+        indention: 1 # Since the headings are not read inside the collapsible block we can indent as 1
+        output-format: asciidoc table
+        output-file: README.adoc
+        output-method: inject
+        template: "// BEGIN_TF_TABLES\n{{ .Content }}\n// END_TF_TABLES" # Define template compatible with AsciiDoc
+        args: "--hide-empty=true" # Do not show empty sections
+        git-push: false
+
+    # This step avoids a commit for each previous step and instead commits everything on a single commit
+    - name: "Commit changes done in the previous steps"
+      uses: stefanzweifel/git-auto-commit-action@v4
+      with:
+        commit_message: "docs(terraform-docs): generate docs and write to README.adoc"