Update project_euler.yml

Author: cclauss

.github/workflows/project_euler.yml

@@ -18,7 +18,8 @@ jobs:
       - uses: astral-sh/setup-uv@v6
       - uses: actions/setup-python@v5
         with:
-          python-version: 3.x
+          python-version: 3.14
+          allow-prerelease: true
       - run: uv sync --group=euler-validate --group=test
       - run: uv run pytest --doctest-modules --cov-report=term-missing:skip-covered --cov=project_euler/ project_euler/
   validate-solutions:
@@ -28,7 +29,8 @@ jobs:
       - uses: astral-sh/setup-uv@v6
       - uses: actions/setup-python@v5
         with:
-          python-version: 3.x
+          python-version: 3.14
+          allow-prerelease: true
       - run: uv sync --group=euler-validate --group=test
       - run: uv run pytest scripts/validate_solutions.py
         env: