chore(api!): mark MsgModuleQuerySafe requests field as non-nullable

[neitdung]

Description

closes: #6582

• Mark MsgModuleQuerySafe.requests as non-nullable
• Modify tests and docs for compatible with the change

Commit Message / Changelog Entry

chore: mark MsgModuleQuerySafe requests field as non-nullable

---

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• Wrote unit and integration tests.
• Updated relevant documentation (docs/).
• Added relevant godoc comments.
• Provide a conventional commit message to follow the repository standards.
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[DimitrisJim]

lgtm, thanks! Not sure what is up with link checker, all links it reports as 404, my browser finds.

[crodriguezvega]

Thanks, @neitdung. Question for the team: should we consider this an API-breaking change?

[DimitrisJim]

should we consider this an API-breaking change?

it is? unless I'm missing something 😄

[crodriguezvega]

should we consider this an API-breaking change?

it is? unless I'm missing something 😄

I might also be missing something, but I thought it could be because of this change. Users of the constructor will need to (slightly) change their code to not pass a slice of pointers, right?

[DimitrisJim]

Users of the constructor will need to (slightly) change their code to not pass a slice of pointers, right?

yup!

[crodriguezvega]

Users of the constructor will need to (slightly) change their code to not pass a slice of pointers, right?

yup!

Ok, then I will push a commit adding a changelog and updating migration docs.