[11.x] Allow customizing TrimStrings::$except (#50901)

* extract method

* formatting

---------

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

Author: grohiro

src/Illuminate/Foundation/Http/Middleware/TrimStrings.php

@@ -62,13 +62,25 @@ protected function transform($key, $value)
     {
         $except = array_merge($this->except, static::$neverTrim);
 
-        if (in_array($key, $except, true) || ! is_string($value)) {
+        if ($this->shouldSkip($key, $except) || ! is_string($value)) {
             return $value;
         }
 
         return Str::trim($value);
     }
 
+    /**
+     * Determine if the given key should be skipped.
+     *
+     * @param  string  $key
+     * @param  array  $except
+     * @return bool
+     */
+    protected function shouldSkip($key, $except)
+    {
+        return in_array($key, $except, true);
+    }
+
     /**
      * Indicate that the given attributes should never be trimmed.
      *