Rollup merge of #77852 - 12101111:fix-bootstrap-doc, r=jonas-schievink
Rollup merge of #77852 - 12101111:fix-bootstrap-doc, r=jonas-schievink

update url in bootstrap README (gcc-rs -> cc-rs)

gcc-rs is renamed to cc-rs 3 years ago.

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