[9.x] Fix (widen) PHPDoc parameter typehint for EnumeratesValues::reject() (#45139)

* Widen parameter typehint for `EnumeratesValues::reject()`

* Add type test

Author: devfrey

src/Illuminate/Collections/Traits/EnumeratesValues.php

@@ -765,7 +765,7 @@ class_basename(static::class), gettype($result)
     /**
      * Create a collection of all elements that do not pass a given truth test.
      *
-     * @param  (callable(TValue, TKey): bool)|bool  $callback
+     * @param  (callable(TValue, TKey): bool)|bool|TValue  $callback
      * @return static
      */
     public function reject($callback = true)

types/Support/Collection.php

@@ -855,6 +855,7 @@ function ($collection, $count) {
 assertType('Illuminate\Support\Collection<int, mixed>', $collection->make(['string' => 'string'])->pluck('string', 'string'));
 
 assertType('Illuminate\Support\Collection<int, User>', $collection->reject());
+assertType('Illuminate\Support\Collection<int, User>', $collection->reject(new User));
 assertType('Illuminate\Support\Collection<int, User>', $collection->reject(function ($user) {
     assertType('User', $user);