Allow users to provide the node-selector, toleration and node-selector-template

[waveywaves]

Tell us about your request

Make it possible for users to mention the node-selector template necessary to install their new uffizzi installation

uffizzi install --node-selector-template gvisor

the above will be translated to a spec for all uffizziclusters created

spec:
  nodeSelectorTemplate: gvisor

The above spec will be picked up by the Uffizzi Cluster Operator and the correct nodeselctor and tolerations spec will be given to the Workloads.

If the nodeselectortemplate flag is not given, the CLI should install . So that users can easily install Uffizzi on minikube. All clusters provided will then be vanilla k3s by default.

Which service(s) is this request for?
cli, app, controller

Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?
Installing and creating clusters on minikube/k3d

Describe the solution you'd like
Mentioned in the request

related to #503

[axisofentropy]

This is fine, just change provider to node-selector and change gke to gvisor. Don't bother with vanilla, just leave null as the default.

[waveywaves]

updating this issue with new changes about nodeselector and tolerations