fix return types (#50461)

Author: imahmood

src/Illuminate/Console/Scheduling/ScheduleRunCommand.php

@@ -271,7 +271,7 @@ protected function shouldInterrupt()
     /**
      * Ensure the interrupt signal is cleared.
      *
-     * @return bool
+     * @return void
      */
     protected function clearInterruptSignal()
     {

src/Illuminate/Foundation/Bootstrap/LoadEnvironmentVariables.php

@@ -94,7 +94,7 @@ protected function createDotenv($app)
      * Write the error information to the screen and exit.
      *
      * @param  \Dotenv\Exception\InvalidFileException  $e
-     * @return void
+     * @return never
      */
     protected function writeErrorAndDie(InvalidFileException $e)
     {

src/Illuminate/Queue/Listener.php

@@ -216,7 +216,7 @@ public function memoryExceeded($memoryLimit)
     /**
      * Stop listening and bail out of the script.
      *
-     * @return void
+     * @return never
      */
     public function stop()
     {

src/Illuminate/Routing/Route.php

@@ -577,7 +577,7 @@ public function setBindingFields(array $bindingFields)
      * Get the parent parameter of the given parameter.
      *
      * @param  string  $parameter
-     * @return string
+     * @return string|null
      */
     public function parentOfParameter($parameter)
     {