[LIFE-810] Support additional pipeline parameters in config validation

[kira-m]

Checklist

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Internal Checklist

• I am requesting a review from my own team as well as the owning team
• I have a plan in place for the monitoring of the changes that I am making (this can include new monitors, logs to be aware of, etc...)

Changes

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• Support additional pipeline parameters when running circleci config validate

Note: I did compile the binary, manually verified that it failed when validating a config containing pipeline.trigger_parameters.github_app.user_id. After I made my changes, compiled again and validation passed.

Rationale

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These parameters are valid and listed in our documentation; we shouldn't throw errors when users actually try to use them