fix Utils/WaitGroup add(delta)

Author: chaz6chez

src/Utils/WaitGroup/Handlers/RevoltWaitGroup.php

@@ -39,7 +39,7 @@ public function __destruct()
     /** @inheritdoc  */
     public function add(int $delta = 1): bool
     {
-        $this->_count++;
+        $this->_count += max($delta, 1);
 
         return true;
     }

src/Utils/WaitGroup/Handlers/RippleWaitGroup.php

@@ -39,7 +39,7 @@ public function __destruct()
     /** @inheritdoc  */
     public function add(int $delta = 1): bool
     {
-        $this->_count++;
+        $this->_count += max($delta, 1);
 
         return true;
     }

src/Utils/WaitGroup/Handlers/SwowWaitGroup.php

@@ -43,8 +43,8 @@ public function __destruct()
     /** @inheritdoc  */
     public function add(int $delta = 1): bool
     {
-        $this->_waitGroup->add($delta);
-        $this->_count++;
+        $this->_waitGroup->add($delta = max($delta, 1));
+        $this->_count += $delta;
 
         return true;
     }