RFR: 8284389: Improve stability of GHA Pre-submit testing by caching cygwin installer

[Christoph Langer]

Make cygwin usage in GHA more reliable

With this change we now attempt to retrieve the cygwin installer from cache every time we need it.
We would also only try to download it once per build job, in the beginning.
During testing we rely on it being cached which will make potential errors more obvious
(e.g. in the download step in the beginning of the build).

I also replaced actions/cache at v2 with v3. Didn't see issues.

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Commit messages:
 - Make cygwin usage in GHA more reliable

Changes: https://git.openjdk.java.net/jdk/pull/8113/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8113&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8284389
  Stats: 55 lines in 1 file changed: 33 ins; 6 del; 16 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8113.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8113/head:pull/8113

PR: https://git.openjdk.java.net/jdk/pull/8113