ci: Add test results upload to Codecov

Add JUnit XML output to pytest and upload test results to Codecov
for detailed test analytics and failure tracking.

Author: github-actions

.github/workflows/tests.yml

@@ -62,7 +62,7 @@ jobs:
         run: uv sync --group dev --all-extras
 
       - name: Run tests
-        run: uv run pytest tests/ -v --tb=short --cov=src/ryandata_address_utils --cov-report=xml --cov-report=term
+        run: uv run pytest tests/ --cov --junitxml=junit.xml -o junit_family=legacy --cov=src/ryandata_address_utils --cov-report=xml --cov-report=term
 
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v4
@@ -72,3 +72,9 @@ jobs:
           flags: unittests
           name: codecov-umbrella
           fail_ci_if_error: false
+
+      - name: Upload test results to Codecov
+        if: ${{ !cancelled() }}
+        uses: codecov/test-results-action@v1
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}