structarmed: use of classNode->isExtended needs implements ExtendedClassAwareRuleInterface

[samsonasik]

Existing code still implements RuleInterface

testo/tools/structarmed/src/Rule/InternalClassMustBeFinalRule.php

Line 17 in de046dd

final readonly class InternalClassMustBeFinalRule implements RuleInterface

This should implements ExtendedClassAwareRuleInterface

Ref example

https://github.com/boundwize/structarmed/blob/ca1371237cc6fe3b41931e8314401921ea1c8f50/src/Rule/Rules/Class_/MustBeFinalRule.php#L15

see documentation

https://boundwize.github.io/structarmed/custom-rules-and-presets/#reading-usage-flags-in-a-custom-rule

[samsonasik]

I created PR:

• Fix InternalClassMustBeFinalRule needs implements ExtendedClassAwareRuleInterface #339

for it.