Review curators permissions

Following #238 (closed) I found many buttons visible to curator, but not usable when not being an editor.

First I think you should review what can and cannot do a curator (when not an editor). I updated the dedicated section in https://gitlab.pasteur.fr/hub/viralhostrangedb/-/blob/update-currator-doc-and-experience/doc/permissions.rst#L71-89 Can you check that the statments are ok with you and the philosohpy behind VHRdb ?

Second I should disable/hide not usable button to curator such as delete virus/host button in data source detail page, or restore button.