As a cloud customer I would like to have a single place for acess and permission docs

[odedponcz]

We should update our documentation around access and permission.
We should add a category called "Access & Permissions" It should hold:

• SSO - https://www.dragonflydb.io/docs/cloud/sso
• Users - https://www.dragonflydb.io/docs/cloud/users
• API Keys - Need to add

Assigned to Ari to re-assign