[release-1.19] Aws eks setup

[istio-testing]

Manual cherrypick required.

#13858 failed to apply on top of branch "release-1.19":

Applying: adding Amazon EKS with Istio setup to platform-setup page
Using index info to reconstruct a base tree...
Falling back to patching base and 3-way merge...
CONFLICT (add/add): Merge conflict in content/en/docs/setup/platform-setup/amazon-eks/index.md
Auto-merging content/en/docs/setup/platform-setup/amazon-eks/index.md
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 adding Amazon EKS with Istio setup to platform-setup page
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

[ericvn]

Closed by #13860