[llvm] workflows: Rewrite build-ci-container to work on larger runners (PR #117353)

[Tom Stellard via llvm-commits]

tstellar wrote:

@boomanaiden154 It looks like the`llvm-premerge-linux-runners` require jobs to use a container and having nested containers doesn't work, so I may have to switch it back to the depot runners.

https://github.com/llvm/llvm-project/pull/117353