chore(dev): upgrade Rust to 1.91.1

[thomasqueirozb]

Summary

Upgrade Rust toolchain to 1.91 (defaults to 1.91.1)

Note that now we're getting this warning:

warning: the following packages contain code that will be rejected by a future version of Rust: num-bigint-dig v0.8.4
note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 1`

To be addressed in a future PR

Vector configuration

NA

How did you test this PR?

CI/MQ

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the no-changelog label to this PR.

References

Notes

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[pront]

Good update. Cleaner code.