fix(Collection::pop()): count < 1 (#54340)

* fix(Collection::pop()): count < 1

If $count = 0 then this method was returning the same as if $count=1. If count<0 then things got worse than that. I think that in this case pop of <1 makes no sense and either we should throw an error, or we should return an empty result. I've gone with an empty result as I can see that being returned by the function anyway.

* Update Collection.php

---------

Co-authored-by: Taylor Otwell <[email protected]>

src/Illuminate/Collections/Collection.php

@@ -986,6 +986,10 @@ public function select($keys)
      */
     public function pop($count = 1)
     {
+        if ($count < 1) { 
+            return new static;
+        }
+
         if ($count === 1) {
             return array_pop($this->items);
         }