chore: Update to Python 3.10.0-rc.1

Author: dbanty

.github/workflows/checks.yml

@@ -13,7 +13,7 @@ jobs:
   test:
     strategy:
       matrix:
-        python: [ 3.6, 3.7, 3.8, 3.9, 3.10.0-beta.3 ]
+        python: [ 3.6, 3.7, 3.8, 3.9, 3.10.0-rc.1 ]
         os: [ ubuntu-latest, macos-latest ]
     runs-on: ${{ matrix.os }}
     steps: