limit it to one python interpretor to solve the problem first

Author: GreatBahram

.github/workflows/tests.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python: [3.6, 3.7, 3.8, 3.9]
+        python: [3.6]
         os: [ubuntu-latest]
     steps:
       - name: Checkout