chore: update release action to support arbitrary refs (#3268)

Author: Panaetius

.github/workflows/release.yml

@@ -6,6 +6,16 @@ on:
         description: New release version
         type: string
         required: true
+      ref:
+        description: Branch/ref to create a release from
+        type: string
+        required: true
+        default: develop
+      target_branch:
+        description: Target branch to create a release to
+        type: string
+        required: true
+        default: master
 
 jobs:
   create-release-pr:
@@ -15,12 +25,12 @@ jobs:
         with:
           fetch-depth: 0
           token: "${{ secrets.RENKUBOT_GITHUB_TOKEN }}"
-          ref: 'develop'
+          ref: '${{ github.event.inputs.ref }}'
       - uses: actions/setup-node@v3
       - name: Create Branch
         run: git checkout -b "release/v${{ github.event.inputs.version }}"
-      - name: Merge Master
-        run: git merge origin/master
+      - name: Merge Target
+        run: git merge "origin/${{ github.event.inputs.target_branch }}"
       - name: Install dependencies
         run: |
           sudo add-apt-repository -y ppa:rmescandon/yq
@@ -31,8 +41,8 @@ jobs:
         id: changelog
         run: |
           echo '{"version": "${{ github.event.inputs.version }}"}' > context.json
-          conventional-changelog -r 1 -p angular -c context.json | pandoc --from markdown --to rst | sed -e '/=======\n/r /dev/stdin' -e 's/=======\n/=======\n\n/' -i CHANGES.rst
-          conventional-changelog -r 1 -p angular -c context.json > release_body.md
+          conventional-changelog -r 1 -p angular -c context.json | sed -e '1,${s/^# /## /}' | pandoc --from markdown --to rst | sed -e '/=======/r /dev/stdin' -e '0,/=======/ s/=======/=======\n/' -i CHANGES.rst
+          conventional-changelog -r 1 -p angular -c context.json | sed -e '1,${s/^# /## /}' > release_body.md
           rm context.json
       - name: Update Chart version
         run: |
@@ -55,7 +65,7 @@ jobs:
           bodyFile: "release_body.md"
           tag: "v${{ github.event.inputs.version }}"
           name: "v${{ github.event.inputs.version }}"
-          commit: "master"
+          commit: "${{ github.event.inputs.target_branch }}"
       - name: Create Pull Request
         uses: actions/github-script@v6
         with:
@@ -67,7 +77,7 @@ jobs:
               owner,
               repo,
               head: 'release/v${{ github.event.inputs.version }}',
-              base: 'master',
+              base: '${{ github.event.inputs.target_branch }}',
               body: [
                 'This PR is auto-generated by',
                 '[actions/github-script](https://github.com/actions/github-script).'