fix(x/tx): sort with oneof field name in amino-json (backport #21782)

[mergify]

Description

The Marshal operation in amino-json needs to take the oneof field name into consideration when ordering the fields, otherwise the resulting JSON will not be properly ordered.
This PR adds checks to the oneof field name when ordering fields.

This issue prevents ledger devices from signing authz grant delegate transactions with a deny-list, since the Validators field was not properly ordered.

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Summary by CodeRabbit

• Bug Fixes

  • Fixed JSON attribute sorting for messages using oneof fields, ensuring consistent and predictable output.

• Improvements

  • Enhanced handling of concurrent writes for better reliability.
  • Improved marshaling of messages with oneof fields, ensuring accurate field names and structure in the output.
  • Updated tests to ensure consistency in JSON encoding across different implementations.

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This is an automatic backport of pull request #21782 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 60cbe2d has failed:

On branch mergify/bp/release/v0.50.x/pr-21782
Your branch is up to date with 'origin/release/v0.50.x'.

You are currently cherry-picking commit 60cbe2db2.
  (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:   x/tx/signing/aminojson/json_marshal.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   tests/integration/tx/aminojson/aminojson_test.go
	both modified:   x/tx/CHANGELOG.md

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