Update the Global Section in the Runner Advanced Config doc

Darren Eastmanrequested to merge
DarrenEastman-main-patch-ca6c into main

What does this MR do?

Update content in the Global section of the Runner Advanced Configuration document

Why was this MR needed?

Documentation review and update for KR 8511](https://gitlab.com/gitlab-com/gitlab-OKRs/-/issues/8511)

What are the relevant issue numbers?

#37933 (closed)

Edited by Darren Eastman

Merge request reports