Update continuous-integration-workflow.yml

Author: tobiasraabe

.github/workflows/continuous-integration-workflow.yml

@@ -18,7 +18,7 @@ jobs:
       fail-fast: false
       matrix:
         os: ['ubuntu-latest', 'macos-latest', 'windows-latest']
-        python-version: ['3.6', '3.7', '3.8', '3.9']
+        python-version: ['3.7', '3.8', '3.9']
 
     steps:
       - uses: actions/checkout@v2