Auto merge of #76409 - jonas-schievink:fix-r-a-on-libcore, r=Mark-Simulacrum
Auto merge of #76409 - jonas-schievink:fix-r-a-on-libcore, r=Mark-Simulacrum

Remove unneeded `#[cfg(not(test))]` from libcore

This fixes rust-analyzer inside these modules (currently it does not analyze them, assuming they're configured out).

aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust