I noticed the related comments (shown below) about the GitHub workflow in the pull request of the JDK-8293214. Actually, the GitHub actions can be triggered manually by using the configuration `on:workflow_dispatch:`. Two related documents for you [2][3] to read.

> I just enable the GitHub Actions after I create the pr. How can I trigger the GHA tests?
> The easiest way is to push an empty commit to your branch.

[1] https://github.com/openjdk/jfx/pull/888
[2] https://docs.github.com/en/actions/managing-workflow-runs/manually-running-a-workflow
[3] https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#workflow_dispatch