Switch to ubuntu-latest action runner

The ubuntu-20.04 runner is deprecated (actions/runner-images#11101), we should just be using the latest.

Author: BryceStevenWilley

.github/workflows/publish.yml

@@ -5,7 +5,7 @@ on: push
 jobs:
   build-n-publish:
     name: Build and publish Python 🐍 distributions 📦 to PyPI
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
     - uses: suffolklitlab/alactions/publish@main
       with: