v1.16: [zk-token-sdk] remove non-pod structs TransferPubkeys and TransferWithFeePubkeys (backport of #32042)

[mergify]

This is an automatic backport of pull request #32042 done by Mergify.
Cherry-pick of d654715 has failed:

On branch mergify/bp/v1.16/pr-32042
Your branch is up to date with 'origin/v1.16'.

You are currently cherry-picking commit d654715ad.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   zk-token-sdk/src/instruction/transfer/without_fee.rs
	modified:   zk-token-sdk/src/zk_token_elgamal/pod/mod.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   zk-token-sdk/src/instruction/transfer/with_fee.rs
	both modified:   zk-token-sdk/src/zk_token_elgamal/convert.rs
	both modified:   zk-token-sdk/src/zk_token_elgamal/pod/instruction.rs

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[codecov]

Codecov Report

Merging #32198 (912d718) into v1.16 (912d718) will not change coverage.
The diff coverage is n/a.

❗ Current head 912d718 differs from pull request most recent head d90d1f3. Consider uploading reports for the commit d90d1f3 to get more accurate results

@@           Coverage Diff           @@
##            v1.16   #32198   +/-   ##
=======================================
  Coverage    81.9%    81.9%           
=======================================
  Files         760      760           
  Lines      207501   207501           
=======================================
  Hits       169991   169991           
  Misses      37510    37510