Auto merge of #125426 - jieyouxu:rmake-support-env-reset, r=saethlin

Update `compiler-builtins` test to not clear essential env vars

Noticed in rust-lang/rust#122580 (comment), the `compiler-builtins` test failed on Windows for a `cargo` invocation because necessary env vars `TMP` and `TEMP` were cleared by `Command::env_clear`, causing temp dir eventually used by codegen to fallback to the Windows directory, which will trigger permission errors.

This PR removes the `env_clear` on the cargo invocation.

r? `@saethlin` (feel free to reroll, since you authored the test)

try-job: x86_64-msvc
try-job: test-various

Author: bors