remove old asm & AnnotationMetadataReader supporting classes; adopt SimpleMetadataReaderFactory

[jdaugherty]

From what I can tell, AnnotationMetadataReader was written for performance reasons. Since Spring 5.2, this was deprecated and finally removed in 6.x. We had copied the file from Spring to get Grails 7 working, but I'm not sure this was the right decision.

Searching the internet + using chatgpt, I noticed this document. Out of curiosity, I removed the AnnotationMetadataReader & replaced it with the upstream Spring reader. All of the tests pass.

I wanted to create this PR as a discussion point since:

1. AnnotationMetadataReader doesn't support @Repeatable
2. Spring acknowledged the performance issues via the rewrite
3. The newer method is both thread safe & readonly - so we could technically cache it now
4. To get spring native working they had to adopt this. I'm not sure we'll ever be able to run with graalvm, but taking steps to support this seems reasonable.
5. This would also have the benefit of simplifying our NOTICE / LICENSE files since both the ASM library & code from Spring can be removed.

I'm going to leave this open for discussion in next week's weekly dev meeting.

[jamesfredley]

This is a good replacement for the changes made in 3.1.x and 7.0.x:

679acbe

a6dd1ec