fix broken github actions matrix

Author: ramunasd

.github/workflows/phpunit.yml

@@ -9,7 +9,6 @@ jobs:
       fail-fast: false
       max-parallel: 4
       matrix:
-        coverage: ['none']
         include:
           - php: '7.0'
             phpseclib: '^2.0'
@@ -65,7 +64,7 @@ jobs:
 
     - name: PHPUnit tests
       run: ./vendor/bin/phpunit --exclude-group proxy
-      if: matrix.coverage == 'none'
+      if: matrix.coverage != 'xdebug'
 
     - name: PHPUnit tests and Log Code coverage
       run: ./vendor/bin/phpunit --exclude-group proxy --coverage-clover=coverage.xml