Rollup merge of #143514 - joshtriplett:macro-test-organization, r=jieyouxu

Organize macro tests a bit more

- Move some macro parsing tests from `tests/ui/parser` to `tests/ui/parser/macro`.

- Most macro tests use `macro` in the name, making it easy to find and run tests relevant to macros. However, a few use `mbe` instead. Rename those to say `macro`.

Author: matthiaskrgr