Feat/support authentication plugins like ldap simple

[alereca]

Description of your changes

Fixes #125

I have:

• [x] Read and followed Crossplane's contribution process.
• [x] Run make reviewable to ensure this PR is ready for review.

How has this code been tested

Added unit test for user controller create and update methods

• UserWithAnAuthPluginThatNotRequiresPassword (for both)