Allow two agents in the same cluster for Fleet managing Fleet

[nickgerace]

Essentially, we need to ensure Hosted Rancher and Harvester work with Fleet in Rancher. This could also benefit standalone Fleet managing standalone Fleet, though that use case will likely be untested to the same degree as Fleet in Rancher for this specific use case.

[nickgerace]

Fleet PR and RC is available, but the rancher/rancher PR needs to be merged before going "To Test"
rancher/rancher#34798

[nickgerace]

cc @deniseschannon this issue is a likely a dupe of another, but I could not find another in harvester/harvester or rancher/rancher

[deniseschannon]

This issue is the root cause to fix: rancher/rancher#34716

[deniseschannon]

I'd like to close this issue in favor of rancher/rancher#34716