[jdk11u-dev] RFR: 8299330: Minor improvements in MSYS2 Workflow handling

[Aleksey Shipilev]

Clean backport to improve GHA reliability.

Additional testing:
 - [ ] GHA

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Commit messages:
 - Backport cf00d09c8c37ee301e1c6657df45777647a834e9

Changes: https://git.openjdk.org/jdk11u-dev/pull/2103/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2103&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8299330
  Stats: 3 lines in 2 files changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2103.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2103/head:pull/2103

PR: https://git.openjdk.org/jdk11u-dev/pull/2103