Use release drafter 7.1.1 (#1875)

* Use documented syntax for GitHub action conditional

https://docs.github.com/en/actions/how-tos/write-workflows/choose-when-workflows-run/control-jobs-with-conditions
shows that `${{ }}` needs to wrap the term of the conditional

* Reduce risk of "No changes" in the changelog by waiting 15 seconds

Issue https://github.com/release-drafter/release-drafter/issues/871
includes this comment:

> PR's associated with commits are coming from GH's GraphQL API, and that
> needs some time to process the same event, that triggered the release
> drafter itself. We added a 15s delay before running the release drafter
> step, ugly but works.

A later comment from the release drafter maintainer says:

> this is high-effort fix with low-effort workaround.
>
> Issue comes from GitHub's Graphql Commit-to-PR relation
> associatedPullRequests, which take some time for github to compute. When
> you push to main and trigger a release-drafter run, you sometimes end
> up being faster than Github's backend and may miss this relation.
>
> To prevent this, simply delay your release-drafter run as @lmagyar suggested.

Testing done:

None.  Rely on GitHub action run when the pull request is merged

* Release drafter 7 uses `with: token` instead of `env: GITHUB_TOKEN`

The https://github.com/release-drafter/release-drafter/pull/1475 breaking
changes section for release drafter 7.0.0 says:

  If you were using a specific access token using env.GITHUB_TOKEN:
  $MY_CUSTOM_TOKEN, migrate to the new token: input

  jobs:
    steps:
      # Before
      - uses: release-drafter/release-drafter@v6
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

      # After
      - uses: release-drafter/release-drafter@v7
        with:
          token: ${{ secrets.GITHUB_TOKEN }}

* Use release drafter 7.1.1

Also assigns a name to the release drafter step so that it is more
easily identified in the web page for GitHub actions.

Explicitly use jenkinsci release-drafter.yml configuration

Release drafter v7 no longer accepts .github as a valid extension.

https://github.com/release-drafter/release-drafter/blob/master/docs/configuration-loading.md
provides an example that uses this syntax for config-name and says that
the _extends syntax accepts the same form.

This form is now used in many Jenkins repositories