Remove nightly from regular CI testing

It's good to seperate workflow files from potentially flaky stuff

Author: Seelengrab

.github/workflows/CI.yml

@@ -31,7 +31,6 @@ jobs:
           - '1.8'
           - '1.9'
           - '1'
-          - 'nightly'
         os:
           - ubuntu-latest
         arch: