Remove python 3.7 from testing workflow.

Author: nickzandbergen

.github/workflows/main.yml

@@ -50,7 +50,7 @@ jobs:
       fail-fast: false
       matrix:
         operating-system: [ubuntu-latest, macos-latest]
-        python-version: ['3.7', '3.8', '3.9', '3.10', '3.11']
+        python-version: ['3.8', '3.9', '3.10', '3.11']
 
     steps:
     - uses: actions/checkout@v2