[4.4] Add missing @return annotations

Author: nicolas-grekas

Pipes/UnixPipes.php

@@ -35,6 +35,9 @@ public function __construct(?bool $ttyMode, bool $ptyMode, $input, bool $haveRea
         parent::__construct($input);
     }
 
+    /**
+     * @return array
+     */
     public function __sleep()
     {
         throw new \BadMethodCallException('Cannot serialize '.__CLASS__);

Pipes/WindowsPipes.php

@@ -88,6 +88,9 @@ public function __construct($input, bool $haveReadSupport)
         parent::__construct($input);
     }
 
+    /**
+     * @return array
+     */
     public function __sleep()
     {
         throw new \BadMethodCallException('Cannot serialize '.__CLASS__);

Process.php

@@ -198,6 +198,9 @@ public static function fromShellCommandline(string $command, string $cwd = null,
         return $process;
     }
 
+    /**
+     * @return array
+     */
     public function __sleep()
     {
         throw new \BadMethodCallException('Cannot serialize '.__CLASS__);