Update prometheus to 4.9.1

[ikavgo]

Proposed Changes

A bug and a race condition were fixed

Types of Changes

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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
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• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

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[michaelklishin]

OCI build failures seem unrelated