Update codecov/codecov-action to v4

Author: 0xced

.github/workflows/continuous-integration.yml

@@ -54,10 +54,11 @@ jobs:
           name: TestResults (${{ runner.os }})
           path: TestResults-*.html
       - name: Upload coverage report to Codecov
-        if: matrix.os == 'ubuntu-latest'
-        uses: codecov/codecov-action@v3
+        if: matrix.os == 'ubuntu-latest' && env.CODECOV_TOKEN != ''
+        uses: codecov/codecov-action@v4
         with:
           files: coverage/*/coverage.cobertura.xml
+          token: ${{ secrets.CODECOV_TOKEN }}
       - name: Upload coverage report to Codacy
         env:
           CODACY_PROJECT_TOKEN: ${{ secrets.CODACY_PROJECT_TOKEN }}