RFR: JMH Pre-Integration Tests workflow [v5]

[Aleksey Shipilev]

> This adds the basic pre-integration test workflow for the project.

Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev
excludes the unrelated changes brought in by the merge/rebase. The pull request contains 12 additional commits since
the last revision:

 - Merge branch 'master' into gh-actions
 - Trying to get non-Linux platforms skip the tests
 - Add JDK 7, disable some excessive configurations from testing
 - Merge branch 'master' into gh-actions
 - Disable commit on push
 - Merge branch 'master' into gh-actions
 - Merge branch 'master' into gh-actions
 - Merge branch 'master' into gh-actions
 - Drop max-parallel from pre-integration workflow
 - Testing more extensive configuration space
 - ... and 2 more: https://git.openjdk.java.net/jmh/compare/441128ab...d9afcc71

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

Changes:
  - all: https://git.openjdk.java.net/jmh/pull/5/files
  - new: https://git.openjdk.java.net/jmh/pull/5/files/48848000..d9afcc71

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jmh&pr=5&range=04
 - incr: https://webrevs.openjdk.java.net/?repo=jmh&pr=5&range=03-04

  Stats: 13 lines in 3 files changed: 11 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jmh/pull/5.diff
  Fetch: git fetch https://git.openjdk.java.net/jmh pull/5/head:pull/5

PR: https://git.openjdk.java.net/jmh/pull/5