[jdk11u-dev] RFR: 8230067: Add optional automatic retry when running jtreg tests

[Christoph Langer]

Backport of JDK-8230067. Needed some manual adaptation in RunTests.gmk. Change to jib-profiles.js does not apply and is not relevant for OpenJDK anyway.

-------------

Commit messages:
 - Backport 72cb073c095014f6babab50c20029ba9f2986f1b

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/457/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=457&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8230067
  Stats: 50 lines in 3 files changed: 37 ins; 11 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/457.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/457/head:pull/457

PR: https://git.openjdk.java.net/jdk11u-dev/pull/457