Fiddle with tests matrix.

Author: pp-mo

.github/workflows/ci-tests.yml

@@ -27,6 +27,7 @@ jobs:
       matrix:
         session: ["tests", "doctests-docs", "doctests-api"]
         python-version: ["3.10", "3.11", "3.12", "3.13"]
+
     defaults:
       run:
         shell: bash -l {0}
@@ -74,13 +75,13 @@ jobs:
           OVERRIDE_TEST_DATA_REPOSITORY=${GITHUB_WORKSPACE}/iris_test_data_download/test_data PYTHONPATH=./tests:$PYTHONPATH pytest -v ./tests
 
       - name: "Run doctests: Docs"
-        if: matrix.session == 'doctests-docs'
+        if: (matrix.session == 'doctests-docs') && (matrix.python_version == "3.13")
         run: |
           cd docs
           pytest --doctest-glob="*.rst" --doctest-continue-on-failure
 
       - name: "Run doctests: API"
-        if: matrix.session == 'doctests-api'
+        if: (matrix.session == 'doctests-api') && (matrix.python_version == "3.13")
         run: |
           cd lib
           pytest --doctest-modules --doctest-continue-on-failure