[jdk16u] RFR: 8260933: runtime/cds/serviceability/ReplaceCriticalClassesForSubgraphs.java fails without CompactStrings

[Aleksey Shipilev]

This stabilizes the test.

Additional testing:
 - [x] Linux x86_64 fastdebug, affected tests with/without `-XX:-CompactStrings`

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Commit messages:
 - Backport 9f0f0c9870b9e09aff4dca20bd1404a1872ac566

Changes: https://git.openjdk.java.net/jdk16u/pull/60/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk16u&pr=60&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8260933
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk16u/pull/60.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk16u pull/60/head:pull/60

PR: https://git.openjdk.java.net/jdk16u/pull/60