Stop trying to upload the coverage if there is no auth token

This fixes build failures on pull requests from forks (where
usually no authentication token for the code coverage is set).

Author: oliverklee

.github/workflows/ci.yml

@@ -73,8 +73,8 @@ jobs:
         run: ./vendor/bin/phpunit --coverage-clover build/coverage/xml
 
       - name: Upload coverage results to Coveralls
-        if: "${{ matrix.coverage != 'none' }}"
         env:
           CODACY_PROJECT_TOKEN: ${{ secrets.CODACY_PROJECT_TOKEN }}
+        if: "${{ matrix.coverage != 'none' }} && ${{ env.CODACY_PROJECT_TOKEN != '' }}"
         run: |
           ./vendor/bin/codacycoverage clover build/coverage/xml