Update test workflow for Python 3.14 support

Added Python 3.13 and 3.14 to the test matrix and updated Codecov upload to run on Python 3.14 with the latest action version. Coverage upload is now non-blocking for CI.

Author: douden

.github/workflows/tests.yml

@@ -18,10 +18,10 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        python-version: ["3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12", "3.13","3.14"]
         include:
         - os: windows-latest
-          python-version: 3.9
+          python-version: "3.14"
 
     runs-on: ${{ matrix.os }}
 
@@ -39,13 +39,13 @@ jobs:
       run: |
         pytest --cov=sphinx_external_toc --cov-report=xml --cov-report=term-missing
     - name: Upload to Codecov
-      if: matrix.python-version == 3.11
-      uses: codecov/codecov-action@v3
+      if: matrix.python-version == '3.14'
+      uses: codecov/codecov-action@v4
       with:
-        name: pytests-py3.11
+        name: pytests-py3.14
         flags: pytests
         file: ./coverage.xml
-        fail_ci_if_error: true
+        fail_ci_if_error: false # uploading coverage should not fail the tests
 
   publish: