Update for the rename doc-builder -> hf-doc-utils
why utils? it's a builder no? ~~@julien-c there was a vote 🙂 https://huggingface.slack.com/archives/C021H1P1HKR/p1646405136644739~~

oh I see you already commeented in the thread as well Thanks ! It looks all good to me (provided `hf-doc-utils` is the name we keep in the end). I'm fine with this name, and `hf-doc-builder` is also fine IMHO ok, this is definitely not a hill I'll die on =) @mishig25 @sgugger 
This PR adapts the job to the upcoming change of name of `doc-builder`.