Fix typo that added a letter to migration template

Signed-off-by: Vitor Mattos <vitor@php.rio>

core/Command/Db/Migrations/GenerateCommand.php

@@ -99,7 +99,7 @@ class {{classname}} extends SimpleMigrationStep {
 	/**
 	 * @param IOutput $output
 	 * @param Closure(): ISchemaWrapper $schemaClosure
-g	 * @param array $options
+	 * @param array $options
 	 */
 	public function postSchemaChange(IOutput $output, Closure $schemaClosure, array $options): void {
 	}