Make Repos and other setting items editable in the Argo CD UI

[ciiay]

Summary

We got feedback from an Argo CD user that it would be nice to have as many as the settings to be editable.

Motivation

Currently it's possible to add/delete things in the repo list, but not update.

Clusters and Projects are editable in UI now, I would like to be able to update repos and other settings using the Argo CD UI

(https://cd.apps.argoproj.io/settings/repos)

Proposal

Create a repo details page which allows updating selected repo information.

[ciiay]

According to the discussion from April 14th Argo Contributor Experience Meeting, some of the settings are designed to be immutable, such as certificates and keys.

For repositories, I confirmed with @rbreeze that there's already a CLI command argocd repo add --upsert to do so, so it should be an easy UI change to make repositories editable.

For account settings, we can open a discussion about what kind of information needs to be editable and worth the change.

[Morriz]

Can this be prioritized? UX wise it is really unfriendly to:

• not validate user input up front
• then serve short lived error bubbles from the api
• navigating away from the form input screen, erasing user input
• and then also NOT allowing to edit the resource

So to start, you could also not navigate away on error, allowing us to keep trial/erroring on your black box UI in the hope to get things right ;p

[Morriz]

Btw, I added a separate UX issue for those concerns: #9217