RFR: 8287336: GHA: Workflows break on patch versions

[Christoph Langer]

This fixes the issue on GHA when the branch contains a patch version.

Here you can see the problem: https://github.com/openjdk-bots/jdk18u/actions/runs/2385040187
And here you see how it looks if it's fixed: https://github.com/RealCLanger/jdk18u/actions/runs/2384983103

I plan to backport this fix to 18u, where the problem currently occurs, immediately.

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Commit messages:
 - JDK-8287336

Changes: https://git.openjdk.java.net/jdk/pull/8888/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8888&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8287336
  Stats: 4 lines in 1 file changed: 3 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8888.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8888/head:pull/8888

PR: https://git.openjdk.java.net/jdk/pull/8888