generate-changelog action does not find commits for final release

[rymsha]

  release_notes:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
        with:
          fetch-depth: 0

      - name: Get previous release tag
        id: get_previous_release_tag
        run: |
          PREVIOUS_RELEASE_TAG=$(git tag --sort=-version:refname --merged | grep -E '^v([[:digit:]]+\.){2}[[:digit:]]+$' | head -1)
          echo ::set-output name=previous_release_tag::$PREVIOUS_RELEASE_TAG
      - name: Generate Release Notes
        uses: enonic/release-tools/generate-changelog@master
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          ZENHUB_TOKEN: ${{ secrets.ZENHUB_TOKEN }}
          PREVIOS_RELEASE_TAG: ${{ steps.get_previous_release_tag.outputs.previous_release_tag }}
          OUTPUT_FILE: changelog.md

      - uses: actions/upload-artifact@v2
        with:
          name: changelog
          path: changelog.md

Now when release happens on tag PREVIOUS_RELEASE_TAG finds the current tag, with 0 commits after it, hence no changes.

Other apps use similar changelog procedure, but tagging happens automatically (release happens on push, not on tag), and GH Action can pick up changes.

[rymsha]

Probable fix - look deeper in get_previous_release_tag if tag found is actual head

[rymsha]

PREVIOUS_RELEASE_TAG=$(git tag --sort=-version:refname --merged | grep -E '^v([[:digit:]]+\.){2}[[:digit:]]+$' | grep -v "$(git describe --tags)" | head -1) should do the trick