NullableTypeDeclarationForDefaultNullValueFixer - fix for nullable with attribute

[kubawerlos]

Fixes #5533

[coveralls]

Coverage decreased (-0.009%) to 91.892% when pulling 068aedb on kubawerlos:fix_NullableTypeDeclarationForDefaultNullValueFixer into 0869890 on FriendsOfPHP:2.18.

[kubawerlos]

@keradus @julienfalque @SpacePossum @localheinz should we extend Tokens::getNextMeaningfulToken to skip PHP 8 attributes as it this case ArgumentsAnalyzer includes it into the type and creates <?php function foo(?#[AnAttribute] string $param = null) {} which is invalid syntax?

[keradus]

attributes are meaningful.
we also fix their content, eg

-#[MyAttribute(array("key" => "value"))]
+#[MyAttribute(['key' => 'value'])]

[keradus]

Thank you @kubawerlos.

[OskarStark]

Thank you very much 🥰