FYI: force-push to master, rewriting 4 commits #2237

Just an FYI in case you notice weirdness in your local copy.

• [7fb314339f] - test: GitHub Actions: Test on Python 3.9 (Christian Clauss) #2230
• [754996b9ec] - doc: replace status badges with new Actions badge (Rod Vagg) #2218
• [2317dc400c] - ci: switch to GitHub Actions (Shelley Vohr) #2210
• [2cca9b74f7] - doc: drop the --production flag for installing windows-build-tools (DeeDeeG) #2206

Two commits since v7.1.0 didn't have proper metadata for our changelog tooling so I've edited those and force pushed master:

• "GitHub Actions: Test on Python 3.9" - added PR-URL and Reviewed-By metadata, also the test: prefix
• "doc: drop the --production flag for installing windows-build-tools" - added PR-URL metadata