feat: introduce multiple guards

[edwardoranj]

Description

Introduced multiple guards on query and update macros to protect them with several guards.

#[update(guards = ["only_admin", "non_reentrant"])]
fn do_something() {
...
}

Fixes #413

How Has This Been Tested?

Added relevant unit test cases

Checklist:

• The title of this PR complies with Conventional Commits.
• I have edited the CHANGELOG accordingly.
• I have made corresponding changes to the documentation.

[cla-idx-bot]

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[lwshang]

Thank you for your contribution! 🙌

Our main development happens on the next branch, so I’ve changed the base branch for this PR. There are a few conflicts to resolve—to speed things up, would you mind granting me permission to edit your PR branch?

You can enable it by following this page.

If you’d prefer to resolve the conflicts yourself, just let me know! Either way, I’m happy to help.

Thanks again for your work! 🚀