build: Update codecov and use token

Update codecov to the latest version and start using the org-wide token for uploads.

See openedx/wg-frontend#179

.github/workflows/ci.yml

@@ -29,7 +29,10 @@ jobs:
     - name: is-es5
       run: npm run is-es5
     - name: Coverage
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v4
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+        fail_ci_if_error: true
     - name: Extract branch name
       shell: bash
       run: echo "##[set-output name=branch;]$(echo ${GITHUB_REF#refs/heads/})"