Fix the default cluster name of the argo app destination

Created by: LinuxSuRen

What type of PR is this?

/kind bug /area devops

What this PR does / why we need it:

As I mentioned in the title. The default cluster name should be in-cluster instead of default.

Before:

After:

Which issue(s) this PR fixes:

Fixes #

Special notes for reviewers:

Does this PR introduced a user-facing change?

None

Additional documentation, usage docs, etc.: