Auto merge of #51285 - Mark-Simulacrum:remove-quote_apis, r=Manishearth

Remove quote_*! macros

This deletes a considerable amount of test cases, some of which we may want to keep. I'm not entirely certain what the primary intent of many of them was; if we should keep them I can attempt to edit each case to continue compiling without the quote_*! macros involved.

Fixes #46849.
Fixes #12265.
Fixes #12266.
Fixes #26994.

r? @Manishearth

diff --cc src/libsyntax/parse/parser.rs
Simple merge