Merge pull request #25009 from nextcloud/backport/25001/stable20

[stable20] Fix column name to check prior to deleting

core/Migrations/Version21000Date20201120141228.php

@@ -40,7 +40,7 @@ public function changeSchema(IOutput $output, Closure $schemaClosure, array $opt
 
 		if ($schema->hasTable('systemtag')) {
 			$table = $schema->getTable('systemtag');
-			if ($table->hasColumn('systemtag')) {
+			if ($table->hasColumn('assignable')) {
 				$table->dropColumn('assignable');
 			}
 		}