docs(external docs): Revise Azure instance type recommendations

[zapdos26]

Summary

Updated Azure recommendations for instance types to specify Azure's ARM64 platform and update the recommendation to match.

Vector configuration

N/A

How did you test this PR?

N/A

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

https://learn.microsoft.com/en-us/azure/virtual-machines/sizes/cobalt-overview

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