Display which plugins are mandatory and can't be removed

Describe the problem/challenge you have

$ velero plugin get
NAME                                                          KIND
velero.io/crd-remap-version                                   BackupItemAction
velero.io/pod                                                 BackupItemAction
velero.io/pv                                                  BackupItemAction
velero.io/service-account                                     BackupItemAction
velero.io/aws                                                 ObjectStore
velero.io/add-pv-from-pvc                                     RestoreItemAction
velero.io/add-pvc-from-pod                                    RestoreItemAction
velero.io/change-pvc-node-selector                            RestoreItemAction
velero.io/change-storage-class                                RestoreItemAction
velero.io/cluster-role-bindings                               RestoreItemAction
velero.io/crd-preserve-fields                                 RestoreItemAction
velero.io/init-restore-hook                                   RestoreItemAction
velero.io/job                                                 RestoreItemAction
velero.io/pod                                                 RestoreItemAction
velero.io/restic                                              RestoreItemAction
velero.io/role-bindings                                       RestoreItemAction
velero.io/service                                             RestoreItemAction
velero.io/service-account                                     RestoreItemAction
velero.io/aws                                                 VolumeSnapshotter

$ velero plugin remove velero.io/service-account
An error occurred: init container velero.io/service-account not found in Velero server deployment

$ velero plugin remove velero.io/aws
An error occurred: init container velero.io/aws not found in Velero server deployment

Describe the solution you'd like

The velero plugin remove command can't remove the system default plugins, it'd be good the UI displays which plugins are mandatory and can't be removed. Furthermore, it'd be good to make the velero plugin remove velero.io/aws work instead velero plugin remove velero/velero-plugin-for-aws:v1.1.0.

Anything else you would like to add:

N/A

Environment:

• Velero version (use velero version): v1.5.2
• Kubernetes version (use kubectl version): v1.19.1
• Kubernetes installer & version: kind
• Cloud provider or hardware configuration: N/A
• OS (e.g. from /etc/os-release): Ubuntu

Vote on this issue!

This is an invitation to the Velero community to vote on issues, you can see the project's top voted issues listed here.
Use the "reaction smiley face" up to the right of this comment to vote.

• :+1: for "The project would be better with this feature added"
• :-1: for "This feature will not enhance the project in a meaningful way"