fix(ci): Incorrect PR title when opening flagsmith-charts PRs (#5821)

Author: khvn26

.github/workflows/platform-docker-build-test-publish.yml

@@ -247,6 +247,8 @@ jobs:
 
       - name: Open a PR bumping Flagsmith to ${{ github.event.release.tag_name }}
         uses: fjogeleit/yaml-update-action@main
+        env:
+          COMMIT_MESSAGE: 'deps: bump Flagsmith from ${{ steps.chart-yaml.outputs.appVersion }} to ${{ steps.version-trim.outputs.version }}'
         with:
           token: ${{ secrets.FLAGSMITH_CHARTS_GITHUB_TOKEN }}
           repository: flagsmith/flagsmith-charts
@@ -256,8 +258,8 @@ jobs:
           branch: deps/bump-flagsmith-${{ steps.version-trim.outputs.version }}
           commitChange: true
           createPR: true
-          message: 'deps: bump Flagsmith from ${{ steps.chart-yaml.outputs.appVersion }} to ${{ steps.version-trim.outputs.version }}'
-          title: '{{message}}'
+          message: ${{ env.COMMIT_MESSAGE }}
+          title: ${{ env.COMMIT_MESSAGE }}
           description: 'Automated PR generated by Flagsmith release [${{ github.event.release.tag_name }}](${{ github.event.release.url }}).'
           valueFile: 'charts/flagsmith/Chart.yaml'
           changes: |