Get extra attributes from Spamcheck response and determine verdict [RUN ALL RSPEC][RUN AS-IF-FOSS]

What does this MR do?

Returns system state as part of the Spamcheck response to show if monitorMode is on/off.

• If monitorMode is true/on, we return the given verdict, log it then reassign it to a nil verdict because Spamcheck is not explicitly rendering verdicts.
• If monitorMode is false/off, we continue with the rest of the spamcheck_verdict function logic.

Additionally, returns #spamcheck_verdict early if we get a NOOP verdict or monitorMode set to true from Spamcheck.

Related to:

• gitlab-com/gl-security/engineering-and-research/automation-team/spam/spamcheck#60
• https://gitlab.com/gitlab-com/gl-security/engineering-and-research/automation-team/spam/spamcheck/-/issues/95

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

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