Description of problem:

After successfully SNO installation, with agentclusterinstall in adding-host status, the spoke does not become available in managedcluster. 

It became available right away after manually increased leaseDurationSeconds in managedcluster. 

Version-Release number of selected component (if applicable):

spoke: 4.12.0/1

hub: 4.12

ACM: 2.6.4 or 2.7.0 

How reproducible:

Reproduced 3 out of 3 times in 2 different envs. 

Steps to Reproduce:

1.  Install and configure SNO via ZTP
2.  After installation completed via agentclusterinstall, wait for managedcluster to become available

Actual results:

• managedcluster does not become available even though spoke is healthy.
• Manually changed leaseDurationSeconds from 60s to 120s, and managedcluster becomes available right away.

Expected results:

• managedcluster becomes available without any workaround

  Additional info: