RFR: 8303085: Runtime problem list cleanup

[Mikhailo Seledtsov]

Identified several Runtime related entries in HotSpot problem list that could be removed because issues are no longer reproducible. Reran corresponding tests multiple times (200-400 times) before removal. See comments in the bug for details.

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Commit messages:
 - 8303085: Runtime problem list cleanup

Changes: https://git.openjdk.org/jdk/pull/12723/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12723&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303085
  Stats: 9 lines in 1 file changed: 0 ins; 7 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/12723.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12723/head:pull/12723

PR: https://git.openjdk.org/jdk/pull/12723