[MAINT] bump codecov version (#908)

bump codecov version

Author: jdkent

.github/workflows/testing.yml

@@ -240,7 +240,7 @@ jobs:
       - name: Download artifacts
         uses: actions/download-artifact@v4
       - name: Upload to CodeCov
-        uses: codecov/codecov-action@v4
+        uses: codecov/codecov-action@v5
         with:
           fail_ci_if_error: true
         env: