RFR: 8370646: TestLargeUTF8Length.java needs lots of memory

[Kelvin Nilsen]

Do not run this test unless the test environment has at least 15 GB of RAM.

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Commit messages:
 - Add @requires maxMemory to TestLargeUTF8Length.java

Changes: https://git.openjdk.org/jdk/pull/28069/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28069&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8370646
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/28069.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28069/head:pull/28069

PR: https://git.openjdk.org/jdk/pull/28069