Rollup merge of #137863 - compiler-errors:unsafe-binder-render, r=oli-obk

Fix pretty printing of unsafe binders

We used to render `unsafe<> i32` as `i32`, and `unsafe<'a> &'a i32` as `for<'a> &'a i32`.

r? oli-obk

Review with whitespace b/c adding a new argument changes some the wrapping of some function calls.

Author: matthiaskrgr