RFR: 8364927: Add @requires annotation to TestReclaimStringsLeaksMemory.java [v4]

[jonghoonpark]

> This change updates `TestReclaimStringsLeaksMemory.java` to properly guard against unsupported GC arguments.
> Previously, the test only checked `@requires vm.gc == "null"`.
> 
> The fix separates the tests and adds explicit `@requires` clauses for each GC configuration to ensure the test only runs when supported.
> 
> This prevents test failures on VMs that do not support the specified GC.
> 
> (This is my first contribution to the JDK. Thank you for your review and guidance.)

jonghoonpark has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains four commits:

 - Merge branch 'openjdk:master' into JDK-8364927-add-requires-annotation
 - remove non-specific GC test item and include ZGC and Shenandoah
   
   Signed-off-by: jonghoonpark <dev at jonghoonpark.com>
 - Merge branch 'master' of https://git.openjdk.org/jdk into JDK-8364927-add-requires-annotation
 - 8364927: Add @requires annotation to TestReclaimStringsLeaksMemory.java
   
   Signed-off-by: jonghoonpark <dev at jonghoonpark.com>

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Changes: https://git.openjdk.org/jdk/pull/26766/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26766&range=03
  Stats: 46 lines in 1 file changed: 42 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/26766.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26766/head:pull/26766

PR: https://git.openjdk.org/jdk/pull/26766