Unable to add K3s cluster #6135

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Checklist:

• I've searched in the docs and FAQ for my answer: https://bit.ly/argocd-faq.
• I've included steps to reproduce the bug.
• I've pasted the output of argocd version.

Describe the bug
I have 2 K3s in my Mac, one has the Argocd. Now, when I connect to another K3s cluster using argocd cluster add <context-name> I get the below error

INFO[0000] ServiceAccount "argocd-manager" already exists in namespace "kube-system"
INFO[0000] ClusterRole "argocd-manager-role" updated
INFO[0000] ClusterRoleBinding "argocd-manager-role-binding" updated
FATA[0001] Failed to establish connection to localhost:8080: dial tcp [::1]:8080: connect: connection refused

To Reproduce

1. create 2 k3s clusters (using k3sup or k3d)
2. Install argocd in one of the cluster following the step described in the argocd doc
3. run argocd cluster add <2nd-cluster-context-name>

Expected behavior
It should add the 2nd cluster?

Version

argocd: v2.0.1+33eaf11.dirty
BuildDate: 2021-04-21T18:44:13Z
GitCommit: 33eaf11
GitTreeState: dirty
GoVersion: go1.16.3
Compiler: gc
Platform: darwin/amd64
argocd-server: v2.0.0+f5119c0
BuildDate: 2021-04-07T06:00:33Z
GitCommit: f5119c0
GitTreeState: clean
GoVersion: go1.16
Compiler: gc
Platform: linux/amd64
Ksonnet Version: v0.13.1
Kustomize Version: v3.9.4 2021-02-09T19:22:10Z
Helm Version: v3.5.1+g32c2223
Kubectl Version: v0.20.4
Jsonnet Version: v0.17.0

INFO[0000] ServiceAccount "argocd-manager" already exists in namespace "kube-system"
INFO[0000] ClusterRole "argocd-manager-role" updated
INFO[0000] ClusterRoleBinding "argocd-manager-role-binding" updated
FATA[0001] Failed to establish connection to localhost:8080: dial tcp [::1]:8080: connect: connection refused