Expand CI to check against various combo's of Crystal, CouchDB, and (backend) OS

[drhuffman12]

Please expand the CI to run the tests against a 'matrix' of version combo's made up of the:

• (needs review/merge) latest 2 versions of CouchDB (2.x? and 3.x?) (See: Drhuffman12/upgrade to crystal 1.1.1 (and 1.2.0-dev) (#1) and expand CouchDB version checks vectorselector/couchdb.cr#2 .)

• (WIP) latest 2 versions of Crystal (stable? and nightly?) (See: Drhuffman12/upgrade to crystal 1.1.1 vectorselector/couchdb.cr#1 .)

  • I ran Crystal 1.1.X locally (passing) and 1.2.x in CI. Both passed. But, it would be good to add them to the 'matrix' for testing.

• multiple OS's (Linux/Mac/Windows) (TBD)
  ... possibly via CircleCI or in GitHub Workflow/Action or otherwise

  • CI Builds are only for Linux. Expand the builds to also cover Windows and MaxOS.
    • Linux
    • MacOS
    • Windows
    • See also:
      • multi-os matrix example broken and orbs outdated circleci/circleci-docs#5611
      • Windows support CircleCI-Public/node-orb#32
      • https://circleci.com/developer/orbs/orb/circleci/node#usage-run_matrix_testing

See:

• drhuffman12/ci_matrix CouchDB (2.x? and 3.x?) drhuffman12/couchdb.cr#2
• Drhuffman12/upgrade to crystal 1.1.1 (and 1.2.0-dev) (#1) and expand CouchDB version checks vectorselector/couchdb.cr#2