Rollup merge of #52627 - Mark-Simulacrum:rustdoc-test-correct, r=alexcrichton
Rollup merge of #52627 - Mark-Simulacrum:rustdoc-test-correct, r=alexcrichton

Compile rustc before building tests for rustdoc

r? @alexcrichton

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