WIP: Clean up manual installation of git-lfs in various docker images

What does this MR do?

This MR cleans up some of the scripting involved in creating runner and runner-helper docker images. Specifically, it consolidates how git-lfs is installed. This MR also addresses Revisit runner-helper alpine image creation (#29944 - closed) by effectively reverting 8a7bfebf

Why was this MR needed?

D.R.Y.

What's the best way to test this MR?

If the pipelines pass and the relevant images are created, we're good.

What are the relevant issue numbers?

closes #29944 (closed)