rustc-ap-rustc_cratesio_shim 121.0.0

Automatically published version of the package `rustc_cratesio_shim` in the rust-lang/rust repository from commit 91db9dcf3730207f63b3dfc33b2c438a769b7517 Thie publishing script for this crate lives at: https://github.com/alexcrichton/rustc-auto-publish