Fix AMBA Service Health deployment conditions

[arjenhuitema]

Overview/Summary

Resolves deployment issues related to Service Health alerts. Previously, Service Health was not deployed when selected unless Azure Monitor Baseline Alerts were also selected.

This PR fixes/adds/changes/removes

1. Fixes deployment conditions for AMBA. Now deploys when enableMonitorBaselines and/or enableServiceHealth is set to Yes
2. Sets enableAMBAConnectivity (and other initiative assignments) to No when enableMonitorBaselines is No and enableServiceHealth is Yes.
3. Sets ALZWebhookServiceUri to null if ambaAgServiceHook is empty; otherwise, it uses the value of ambaAgServiceHook. Single platform was missed in Fixes empty parameters for amba service hook and email contact #1818
4. Sets ALZMonitorActionGroupEmail to null if ambaAgEmailContact is empty; otherwise, it uses the value of ambaAgEmailContact. Single platform was missed in Fixes empty parameters for amba service hook and email contact #1818

Breaking Changes

None

Testing Evidence

Test 1: Dedicated platform

• AMBA: No
• Service Health: Yes

Test 2: Dedicated platform

• AMBA: Yes
• Service Health: Yes

Test 3: Single platform

• AMBA: No
• Service Health: Yes

Test 4: Single platform

• AMBA: Yes
• Service Health: Yes

Testing URLs

Azure Public

As part of this Pull Request I have

• Checked for duplicate Pull Requests
• Associated it with relevant issues, for tracking and closure.
• Ensured my code/branch is up-to-date with the latest changes in the main branch
• Performed testing and provided evidence.
• Ensured contribution guidance is followed.
• Updated relevant and associated documentation.
• Updated the "What's New?" wiki page (located: /docs/wiki/whats-new.md)

[Springstone]

LGTM. Recommend merging after PolicyRefresh