Update ci.yaml

Author: JLBegin

.github/workflows/ci.yaml

@@ -8,7 +8,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-20.04, ubuntu-22.04, windows-latest]
-        python-version: ["3.9""3.12"]
+        python-version: ["3.9", "3.12"]
 
     runs-on: ${{ matrix.os }}