Rollup merge of #55343 - Keruspe:remap-debuginfo-release, r=alexcrichton
Rollup merge of #55343 - Keruspe:remap-debuginfo-release, r=alexcrichton

rustbuild: fix remap-debuginfo when building a release

Fallback to the release number as we can't get the git commit sha as we're not in a git repository.

Fixes #55341

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