7903857: apidiff: Include test run in GitHub Actions workflow

[sormuras]

Please review this change to actually run ApiDiff's self-tests on all three major platforms.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Integration blocker

 ⚠️ Title mismatch between PR and JBS for issue CODETOOLS-7903857

Issue

• CODETOOLS-7903857: Include test run in GitHub Actions workflow (Enhancement - P4) ⚠️ Title mismatch between PR and JBS.

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/apidiff.git pull/23/head:pull/23
$ git checkout pull/23

Update a local copy of the PR:
$ git checkout pull/23
$ git pull https://git.openjdk.org/apidiff.git pull/23/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 23

View PR using the GUI difftool:
$ git pr show -t 23

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/apidiff/pull/23.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back cstein! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[mlbridge]

Webrevs

• 03: Full - Incremental (db262374)
• 02: Full - Incremental (50ba912a)
• 01: Full - Incremental (f68c3e3c)
• 00: Full (49fd0e55)

[pavelrappo]

How did you verify that the updated workflow works?

[sormuras]

How did you verify that the updated workflow works?

They did not! See latest failed runs at https://github.com/sormuras/apidiff/actions/workflows/test.yml