Fix PHPUnit multisite test workflow parameters

Correct the parameter order in install-wp-tests.sh call:
- Parameter 6 should be skip-database-creation (false)
- Parameter 7 should be multisite flag

This fixes the multisite tests that were failing because the
multisite flag was being passed as parameter 6 instead of 7.

🤖 Generated with [Qoder][https://qoder.com]

.github/workflows/phpunit.yml

@@ -51,7 +51,7 @@ jobs:
 
       - name: Install WordPress test suite
         run: |
-          bash bin/install-wp-tests.sh wordpress_test root root 127.0.0.1 ${{ matrix.wp }} ${{ matrix.multisite && 'true' || 'false' }}
+          bash bin/install-wp-tests.sh wordpress_test root root 127.0.0.1 ${{ matrix.wp }} false ${{ matrix.multisite && 'true' || 'false' }}
 
       - name: Run PHPUnit tests
         run: |