Fix Annotation.refersToParamOf to work with parameter references outside of Ident or This

[mbovel]

Currently, Annotations.refersToParamOf assumes that all TermParamRef types will only appear as the (root) type of Ident or This trees:

scala3/compiler/src/dotty/tools/dotc/core/Annotations.scala

Lines 75 to 82 in 912b6f2

	def refersToParamOf(tl: TermLambda)(using Context): Boolean =
	val args = arguments
	if args.isEmpty then false
	else tree.existsSubTree:
	case id: (Ident | This) => id.tpe.stripped match
	case TermParamRef(tl1, _) => tl eq tl1
	case _ => false
	case _ => false

This assumption can be invalidated, for example when trees are generated by macros.

See #22001 (comment) for prior discussion. I proposed two fixes there.

To do:

• write test-cases,
• find the minimal fix: refersToParamOf should visit the least possible number of trees and types.