Use 3.10 for Github actions (#1198)

* Use 3.10 for Github actions

Co-authored-by: Marc Mueller <[email protected]>
Co-authored-by: Pierre Sassoulas <[email protected]>

Author: cdce8p

.github/workflows/ci.yaml

@@ -119,7 +119,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10-dev]
+        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
     outputs:
       python-key: ${{ steps.generate-python-key.outputs.key }}
     steps:
@@ -163,7 +163,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10-dev]
+        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
     steps:
       - name: Check out code from GitHub
         uses: actions/[email protected]
@@ -244,7 +244,7 @@ jobs:
     runs-on: windows-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10-dev]
+        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
     outputs:
       python-key: ${{ steps.generate-python-key.outputs.key }}
     steps:
@@ -288,7 +288,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.6, 3.7, 3.8, 3.9, 3.10-dev]
+        python-version: [3.6, 3.7, 3.8, 3.9, "3.10"]
     steps:
       - name: Set temp directory
         run: echo "TEMP=$env:USERPROFILE\AppData\Local\Temp" >> $env:GITHUB_ENV