ci: use oidc for codecov access

Author: jason-famedly

.github/workflows/famedly-tests.yml

@@ -256,7 +256,7 @@ jobs:
       - name: Codecov - Upload coverage
         uses: codecov/codecov-action@v5
         with:
-          token: ${{secrets.CODECOV_TOKEN}}
+          use_oidc: true
 
   sytest:
     if: ${{ !failure() && !cancelled() }}