update doc for release preparation and also after release

Signed-off-by: sagargurung1001@gmail.com <sagargurung1001@gmail.com>

README.md

@@ -586,6 +586,8 @@ npm run watch
 5. Do QA and fixes of bugs in the release branch
 6. Update `.github/workflows/nighlty-ci-release-branch.yml` to run nightly on release branch
 7. Merge the release branch into the `master` branch, to get all good changes also into the current development
+8. Add change log in `CHANGELOG.md` with version to be released
+9. If any unreleased changes in `CHANGELOG.md` then add to the newly added change log
 
 ##### b. In case of a patch version
 
@@ -599,3 +601,7 @@ npm run watch
    e.g: `git tag v2.0.6-20220928-nightly -m "v2.0.6-20220928-nightly"`
 2. Push the tag to the `auto-release`  branch: `git push origin release/<version>:auto-release --tags -f`
 3. Approve the deployment in GitHub actions
+
+#### 3. After Release
+1. Generate all the change logs for the new version of app on GitHub
+   e.g. for newly created tag vX.X.X, follow `https://github.com/nextcloud/integration_openproject/releases/tag/vX.X.X`