[CI] Temporarly disable phpunit7 until it starts working again (#2392)

.github/workflows/tests.yml

@@ -7,18 +7,19 @@ on:
     branches: [ master ]
 
 jobs:
-  phpunit7:
-    runs-on: ubuntu-20.04
-    strategy:
-      matrix:
-        php-versions: ['7.1', '7.2', '7.3']
-    steps:
-      - uses: actions/checkout@v2
-      - uses: shivammathur/setup-php@v2
-        with:
-          php-version: ${{ matrix.php-versions }}
-      - run: composer global require phpunit/phpunit ^7
-      - run: phpunit --configuration=phpunit.xml --include-path=lib/
+  # TODO: return back when fixed https://github.com/RSS-Bridge/rss-bridge/issues/2391
+  # phpunit7:
+  #   runs-on: ubuntu-20.04
+  #   strategy:
+  #     matrix:
+  #       php-versions: ['7.1', '7.2', '7.3']
+  #   steps:
+  #     - uses: actions/checkout@v2
+  #     - uses: shivammathur/setup-php@v2
+  #       with:
+  #         php-version: ${{ matrix.php-versions }}
+  #     - run: composer global require phpunit/phpunit ^7
+  #     - run: phpunit --configuration=phpunit.xml --include-path=lib/
 
   phpunit8:
     runs-on: ubuntu-20.04