Issue title: Staging - [Alerting] On-Prem Machines Heartbeating By Queue alert
 Issue body: :broken_heart: Metric state changed to *alerting*

> One or more queues of on-prem Helix machines had a heartbeat rate below 80%. This may indicate a deployment, the addition of new machines that are not yet active, or a systemic problem with the machines.

  - *Percentage Heartbeating {QueueName=osx.1015.amd64}* 42.857142857142854


![Metric Graph](https://dotnetgrafanastaging.blob.core.windows.net/grafana/h8bUiuBCEff6a84furXnngOhJU8VmH.png)

[Go to rule](https://dotnet-eng-grafana-staging.westus2.cloudapp.azure.com/d/queueOverview/on-premises-helix-queue-status?tab=alert&viewPanel=9&orgId=1)

@dotnet/dnceng, please investigate



<details>
<summary>Automation information below, do not change</summary>

Grafana-Automated-Alert-Id-d2356d84cf3e43ea952d81de941eaa76

</details>

 Comments: 
 Comment 0: @ilyas1974 I initially took this cos I thought it might be the rollout, but it's staging.  Looks like a bunch of the dci-macpro-* machines are grumpy, I'll take a look then self-unassign.
 Comment 1: Just looks like they got updated and lost their systemctl entries in the update.  Self-un-assigned.
 Comment 2: :green_heart: Metric state changed to *ok*

> One or more queues of on-prem Helix machines had a heartbeat rate below 80%. This may indicate a deployment, the addition of new machines that are not yet active, or a systemic problem with the machines.



![Metric Graph](https://dotnetgrafanastaging.blob.core.windows.net/grafana/6nmKFdyy82fDz0uj4AnBZI5hlkPHj8.png)

[Go to rule](https://dotnet-eng-grafana-staging.westus2.cloudapp.azure.com/d/queueOverview/on-premises-helix-queue-status?tab=alert&viewPanel=9&orgId=1)
{'source': 'GithubIssues', 'repo_name_with_owner': 'dotnet/arcade', 'issue_id': 1296330331, 'repo_stars': 586.0}