Update python-package.yml

Author: ageiss2

.github/workflows/python-package.yml

@@ -16,10 +16,10 @@ jobs:
     strategy:
       matrix:
         os: [ ubuntu-latest ]
-        python-version: [ 3.8, 3.9, '3.10', '3.11', '3.12' ]
+        python-version: [ '3.8', '3.9', '3.10', '3.11', '3.12' ]
         include:
-          - os: ubuntu-20.04
-            python-version: 3.7
+          - os: ubuntu-18.04
+            python-version: '3.7'
 
     steps:
       - uses: actions/checkout@v2