Remove "Add tokens" button from the Tokens app

[john-light]

In the Dandelion template, members cannot be onboarded through the Tokens app. They are onboarded via Token Request. When trying to mint a token using the Tokens app with the Dandelion template, the user gets a generic "this action is impossible" error (see screenshot below).

I think it would make sense, and provide a better overall experience, if the Dandelion template used a modified Tokens app that has the "Add tokens" button removed.