Tests: Remove redundant unregister call in block bindings tear down

Only block bindings sources registered in the tests should get unregistered.

Follow-up for [57375].
See #60282.
Props czapla.



git-svn-id: https://develop.svn.wordpress.org/trunk@57385 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/block-bindings/register.php

@@ -26,7 +26,6 @@ public function tear_down() {
 			if ( str_starts_with( $source_name, 'test/' ) ) {
 				unregister_block_bindings_source( $source_name );
 			}
-			unregister_block_bindings_source( $source_name );
 		}
 
 		parent::tear_down();