Enable fail-fast for wheels build, in an attempt to free up workers.

.github/workflows/pythonwheels.yml

@@ -18,7 +18,7 @@ jobs:
           - os: ubuntu-latest
             python-version: '3.x'
           # path encoding
-      fail-fast: false
+      fail-fast: true
 
     steps:
     - uses: actions/checkout@v2