Create release branch GitHub workflow

.github/workflows/create_release_branch.yml

@@ -0,0 +1,94 @@
+name: Create Release Branch Workflow
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: "Release version"
+        required: true
+        type: string
+      branch_name:
+        description: "Release branch name"
+        required: true
+        type: string
+      commit_sha:
+        description: "Optional commit SHA to start release branch from. By default, it will use the latest commit on the main branch."
+        required: false
+        type: string
+
+jobs:
+  create-release-branch:
+    runs-on: ubuntu-latest
+    steps:
+
+      - name: Create GitHub App Token
+        uses: actions/create-github-app-token@v2
+        id: app-token
+        with:
+          app-id: ${{ vars.MONGODB_KUBERNETES_APP_ID }}
+          private-key: ${{ secrets.MONGODB_KUBERNETES_APP_PRIVATE_KEY }}
+
+      - name: Checkout repository (master)
+        if: ${{ github.event.inputs.commit_sha == '' }}
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          token: ${{ steps.app-token.outputs.token }}
+          ref: ${{ github.head_ref }}
+
+      - name: Checkout repository (commit SHA))
+        if: ${{ github.event.inputs.commit_sha != '' }}
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          token: ${{ steps.app-token.outputs.token }}
+          ref: ${{ github.event.inputs.commit_sha }}
+
+      - name: Get GitHub App User ID
+        id: get-user-id
+        run: echo "user-id=$(gh api "/users/${{ steps.app-token.outputs.app-slug }}[bot]" --jq .id)" >> "$GITHUB_OUTPUT"
+        env:
+          GH_TOKEN: ${{ steps.app-token.outputs.token }}
+
+      - name: Set up Git
+        id: setup-git
+        run: |
+          git config --global user.name '${{ steps.app-token.outputs.app-slug }}[bot]'
+          git config --global user.email '${{ steps.get-user-id.outputs.user-id }}+${{ steps.app-token.outputs.app-slug }}[bot]@users.noreply.github.com'
+
+      - name: Check if release branch already exists
+        id: check-branch
+        run: |
+          if git show-ref --verify --quiet refs/heads/${{ github.event.inputs.branch_name }}; then
+            echo "Release branch ${{ github.event.inputs.branch_name }} already exists."
+            git checkout ${{ github.event.inputs.branch_name }}
+          else
+            echo "create_new_branch=true" >> $GITHUB_ENV
+          fi
+
+      - name: Create release branch
+        id: create-branch
+        if: env.create_new_branch == 'true'
+        run: |
+          git checkout -b ${{ github.event.inputs.branch_name }}
+          git push --set-upstream origin ${{ github.event.inputs.branch_name }}
+        env:
+          GH_TOKEN: ${{ steps.app-token.outputs.token }}
+
+      - name: Replace version in release.json
+        id: replace-version
+        run: |
+          jq  --arg version "${{ github.event.inputs.version }}" '.mongodbOperator=$version' release.json > tmp_release.json
+          mv tmp_release.json release.json
+          git add release.json
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v7
+        with:
+          token: ${{ steps.app-token.outputs.token }}
+          sign-commits: true
+          commit-message: Release version `${{ github.event.inputs.version }}`
+          title: Release version `${{ github.event.inputs.version }}`
+          signoff: false
+          delete-branch: false
+          branch: bump-${{ github.event.inputs.version }}-version
+          draft: true