Investigate semantic-rust macro tests

[joshvera]

@p-alik has graciously added the semantic-rust package but we've had to exclude some macro corpus tests due to parsing issues.

See https://github.com/github/semantic/pull/551 for details.

[p-alik]

https://github.com/github/semantic/blob/25afb3fbb9c265fc5a986d29bc016d4c7d64e8d3/semantic-ast/src/AST/Test.hs#L79 exampleParser looks for --- but in macros.txt two examples end with ----.

• https://github.com/tree-sitter/tree-sitter-rust/blob/40620bf4097cbc9cea79504d7e877865df43a19e/corpus/macros.txt#L32
• https://github.com/tree-sitter/tree-sitter-rust/blob/40620bf4097cbc9cea79504d7e877865df43a19e/corpus/macros.txt#L90