[connector/signaltometricsconnector]: Generalize ExtractGrokPatterns validation for all metric types

[simitt]

Component(s)

connector/signaltometricsconnector

Describe the issue you're reporting

As a follow up to https://github.com/open-telemetry/opentelemetry-collector-contrib/pull/40113/files#r2093058092, review how to handle config validation for all funcs that return map (or other non-primitives) and generalize validations such as ExtractGrokPatterns.

[github-actions]

Pinging code owners:

• connector/signaltometrics: @ChrsMark @lahsivjar

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[lahsivjar]

/labels -needs-triage