Fix issues in changed files

- Initializes $return in Process::insert
- Update the type hint of dba::fetch
- Remove unused $a parameter in worker_init()
- Fix uses

include/dba.php

@@ -659,7 +659,7 @@ class dba {
 	/**
 	 * @brief Fetch a single row
 	 *
-	 * @param PDOStatement|mysqli_result|mysqli_stmt $stmt statement object
+	 * @param mixed $stmt statement object
 	 * @return array current row
 	 */
 	public static function fetch($stmt) {

mod/worker.php

@@ -4,11 +4,10 @@
  * @brief Module for running the worker as frontend process
  */
 
-use Friendica\Core\Worker;
 use Friendica\Core\Config;
-use Friendica\Core\PConfig;
+use Friendica\Core\Worker;
 
-function worker_init($a){
+function worker_init(){
 
 	if (!Config::get("system", "frontend_worker")) {
 		return;

scripts/worker.php

@@ -6,8 +6,8 @@
  */
 
 use Friendica\App;
-use Friendica\Core\Worker;
 use Friendica\Core\Config;
+use Friendica\Core\Worker;
 
 // Ensure that worker.php is executed from the base path of the installation
 if (!file_exists("boot.php") && (sizeof($_SERVER["argv"]) != 0)) {

src/Model/Process.php

@@ -23,6 +23,8 @@ class Process extends BaseObject
 	 */
 	public static function insert($command, $pid = null)
 	{
+		$return = true;
+
 		dba::transaction();
 
 		if (!dba::exists('process', ['pid' => getmypid()])) {