JCore brownfield alerts - fix query for AVD Agent Health

[JCoreMS]

Overview/Summary

This fixes a noted issue with the alert "AVD-HP-VM-HlthChkFailure-(hostpoolname)" in which the Session Host Name was not populating due to the query having an extra space in the parse line for the Resource Id.

Noted space is after the quotes before '/providers' and removed for both the BICEP and ARM template.

| parse ....... SessionHostRG " /providers/Microsoft.Compute/virtualMachines/" SessionHostName vs | parse ....... SessionHostRG "/providers/Microsoft.Compute/virtualMachines/" SessionHostName

This PR fixes/adds/changes/removes

1. Query for the AVD-HP-VM-HlthChkFailure alert to ensure the Session Host Name is returned in the results
2. Adjusted threshold for Azure Files availability from 99 to 99.99 due to degradation noted prior to hitting the threshold which is too low.

Breaking Changes

1. N/A

Testing Evidence

Tested query in Log Analytics to verify issue was resolved and was noted while reviewing for another customer.

As part of this Pull Request I have

• [X] Read the Contribution Guide and ensured this PR is compliant with the guide
• [X] Ensured the resource API versions in .bicep file/s I am adding/editing are using the latest API version possible
• [X] Checked for duplicate Pull Requests
• [X] Associated it with relevant GitHub Issues
• [X] (AVD LZA Team Only) Associated it with relevant ADO Items
• [X] Ensured my code/branch is up-to-date with the latest changes in the main branch
• [X] Performed testing and provided evidence.
• [X] Updated relevant and associated documentation (e.g. Contribution Guide, Module READMEs, Docs etc.)

[danycontre]

@JCoreMS thanks for your contribution