Auto merge of #2273 - JohnTitor:docgen-cleanup, r=JohnTitor
Auto merge of #2273 - JohnTitor:docgen-cleanup, r=JohnTitor

Use inlined script to upload docs to gh-pages

...because the action we're using is outdated. Confirmed that it worked on my fork: https://github.com/JohnTitor/libc/actions/runs/1002739375
r? `@ghost`

rust-lang/libc,rust-lang/libc,rust-lang/libc