Resolve the ExpressRoute QoS remediation issue

[arjenhuitema]

Overview/Summary

Although the alerts were generated correctly, the policy never reached a compliant state. This occurred because the values in the Existence Condition didn't match the actual alert values.

Fixes #356

This PR fixes/adds/changes/removes

1. Corrected values for numberOfEvaluationPeriods and minFailingPeriodsToAlert within the existenceCondition

Evidence

Alerts created

Remediation

Policy compliance

Breaking Changes

None.

As part of this Pull Request I have

• [X] Read the Contribution Guide and ensured this PR is compliant with the guide
• [X] Checked for duplicate Pull Requests
• [X] Associated it with relevant GitHub Issues or ADO Work Items (Internal Only)
• [X] Ensured my code/branch is up-to-date with the latest changes in the main branch
• [X] Ensured PR tests are passing
• [X] Updated relevant and associated documentation (e.g. Contribution Guide, Docs etc.)