[Self-Managed]: Secondary agent remains Healthy even after unenrolling existing fleet-server.

**Kibana version:** 8.7 BC3 Kibana self-managed environment

**Host OS:** Windows Fleet-Server and Ubuntu Secondary agent.

**Build details:**
VERSION: 8.7 BC3
BUILD: 60783
COMMIT: 4ed6814a5dd5532a30bde9b34354a949d9166ae9
Artifact Link: https://staging.elastic.co/8.7.0-6a78ce9a/summary-8.7.0.html

**Preconditions:**
1. 8.7 BC3 Kibana self-managed environment should be available.
2. Fleet Server should be installed.
3. Secondary agent should be installed and running Healthy.

**Steps to reproduce:**
1. Navigate to Fleet>Agents tab.
2. Force Unenroll the existing fleet-server from Fleet>Agents UI.
3. Observe installed secondary agent remains Healthy.
4. Observe new data and logs continues to generate.

**Note:**
- We have observed that the secondary agent remains Healthy even after 10 hours of unenrolling existing Fleet server.
- On running `.\elastic-agent.exe uninstall` command for the Fleet-Server, the secondary agent got Offline, however data and logs continues to generate.

**Logs:**

**Uninstalled Fleet Server logs:**
[[Uninstalled Fleet-Server]elastic-agent-diagnostics-2023-02-21T04-36-10Z-00.zip](https://github.com/elastic/elastic-agent/files/10789780/Uninstalled.Fleet-Server.elastic-agent-diagnostics-2023-02-21T04-36-10Z-00.zip)

**Secondary Agent running Healthy without fleet-server logs:**
[[Secondary]elastic-agent-diagnostics-2023-02-21T04-41-51Z-00.zip](https://github.com/elastic/elastic-agent/files/10789782/Secondary.elastic-agent-diagnostics-2023-02-21T04-41-51Z-00.zip)

**Expected Result:**
As per our understanding, secondary agent should get offline and no new data should be generated after unenrolling existing fleet-server.

**Screen Recording:**

https://user-images.githubusercontent.com/77374876/220252337-83fa0db3-657c-4ef2-b327-9a9fba121f0b.mp4

https://user-images.githubusercontent.com/77374876/220252364-d8a5db4b-f4fb-4c10-9b7c-90b56ab968a8.mp4

https://user-images.githubusercontent.com/77374876/220252405-e22bb1c2-8edc-4697-a8d9-78c4ff70455a.mp4

**On running Uninstall command for fleet-server:**

https://user-images.githubusercontent.com/77374876/220254916-8543d35f-2e09-4b89-adb4-0159f9047c4e.mp4