[jdk21u] RFR: 8313752: InstanceKlassFlags::print_on doesn't print the flag names

[Aleksey Shipilev]

Clean backport to fix JDK 21 regression in diagnostic printing.

Additional testing:
 - [x] New test passes with the fix, fails without it

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Commit messages:
 - Backport 735b16a6969ba5998b4f809927e5ac42a7e72d2d

Changes: https://git.openjdk.org/jdk21u/pull/87/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=87&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8313752
  Stats: 7 lines in 4 files changed: 3 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/jdk21u/pull/87.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/87/head:pull/87

PR: https://git.openjdk.org/jdk21u/pull/87