Merge branch '6.3' into 6.4

* 6.3:
  [Mime] Fix lowest versions of deps
  [VarDumper] Fix calling scope detection inside magic accessors
  [Validator] add missing German translations
  [Serializer] Fix denormalizing abstract part headers in MimeMessageNormalizer
  [Form] Remove an obsolete phpdoc comment
  [Webhook] Allow slash in webhook type
  [FrameworkBundle][Workflow] Throw exception is workflow.xxx.transitions is not an array

FormTypeGuesserInterface.php

@@ -40,13 +40,6 @@ public function guessMaxLength(string $class, string $property);
     /**
      * Returns a guess about the field's pattern.
      *
-     * - When you have a min value, you guess a min length of this min (LOW_CONFIDENCE)
-     * - Then line below, if this value is a float type, this is wrong so you guess null with MEDIUM_CONFIDENCE to override the previous guess.
-     * Example:
-     *  You want a float greater than 5, 4.512313 is not valid but length(4.512314) > length(5)
-     *
-     * @see https://github.com/symfony/symfony/pull/3927
-     *
      * @return Guess\ValueGuess|null
      */
     public function guessPattern(string $class, string $property);