Update CI.yml

Author: ChrisRackauckas

.github/workflows/CI.yml

@@ -19,7 +19,7 @@ jobs:
           # Disabling Windows tests as it's known to not work:
           # https://github.com/SciML/diffeqpy/pull/86#issuecomment-1011675735
           # - windows-latest
-        python-version: ['3.9', '3.13']
+        python-version: ['3.10', '3.13']
       fail-fast: false
     name: Test ${{ matrix.os }} ${{ matrix.architecture }}
       Python ${{ matrix.python-version }}
@@ -47,3 +47,4 @@ jobs:
         with:
           file: ./coverage.xml
           name: codecov-umbrella
+