comb through documentation and deep link "Don't use EFS"

As discussed in our last 1:1, @sahbabou - please go through the documentation and identify as many locations as you can where someone might conceivably think to themselves "Hmm, EFS might be a good idea" and make an MR linking to https://docs.gitlab.com/ee/administration/high_availability/nfs.html#avoid-using-awss-elastic-file-system-efs

Let's use this issue as a tracking issue for any MRs that result.

(If anyone else wants to join in - please feel free!)