RFR: 8238263: Create at-requires mechanism for containers

[Harold Seigel]

Please review this change to add an @requires mechanism called "jdk.containerized" to help mark tests that are incompatible with containers.  Users would add "@requires jdk.containerized != true" to the incompatible tests and then use "make test ... OPTIONS=-Djdk.containerized=true" or "bash jib.sh mach5 -- remote-build-and-test ... --test-make-args JTREG=OPTIONS=-Djdk.containerized=true" to exclude those tests when testing with containers.

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Commit messages:
 - 8238263: Create at-requires mechanism for containers

Changes: https://git.openjdk.java.net/jdk/pull/844/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=844&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8238263
  Stats: 4 lines in 2 files changed: 2 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/844.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/844/head:pull/844

PR: https://git.openjdk.java.net/jdk/pull/844