increased timeout since python 3.11 tests slower

Author: wolph

.github/workflows/main.yml

@@ -8,7 +8,7 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
-    timeout-minutes: 2
+    timeout-minutes: 4
     strategy:
       matrix:
         python-version: ['3.7', '3.8', '3.9', '3.10', '3.11-dev']