Is there an existing issue for this?

• I have searched the existing issues

Does this enhancement require public documentation?

• I have added an Acceptance Criteria item for adding and/or adjusting public documentation (if applicable)

Problem Statement

To make it possible to not run the diagnostics server as part of the manager, we've added DisableRunningDiagnosticsServer flag to the Config struct. It's needed in KGO so that we can run a manager without the diagnostics server as otherwise it wouldn't be possible to run multiple instances of the manager.

The goal of this issue is to remove this flag and move the logic responsible for running the diagnostics server outside of the manager (from https://github.com/Kong/kubernetes-ingress-controller/blob/224424e7765e7cce1e584c143d7561776a7e7005/internal/manager/run.go#L497 to https://github.com/Kong/kubernetes-ingress-controller/blob/04f900c99de407b422b242e746cd9b5097751cb0/internal/cmd/rootcmd/run.go#L40).

Proposed Solution

Move code that runs the diagnostics server out of manager.Manager. It can be done similarly to the health check server that's run in https://github.com/Kong/kubernetes-ingress-controller/blob/04f900c99de407b422b242e746cd9b5097751cb0/internal/cmd/rootcmd/run.go#L40.

Additional information

No response

Acceptance Criteria

• DisableRunningDiagnosticsServer in Config struct is removed
• By default, manager.Manager is run without a diagnostics server