[jdk21u] RFR: 8309746: Reconfigure check should include make/conf/version-numbers.conf

[Aleksey Shipilev]

Clean backport to improve build system support.

Additional testing:
 - [x] Checking that reconfigure message triggers after touching `make/conf/version-numbers.conf`

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Commit messages:
 - Backport 955fc2fabafc4c4d79d137bf86194228d5cf8ad8

Changes: https://git.openjdk.org/jdk21u/pull/16/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=16&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309746
  Stats: 5 lines in 1 file changed: 3 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u/pull/16.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/16/head:pull/16

PR: https://git.openjdk.org/jdk21u/pull/16