POST host_facotry_tokenswith invalid cidr should return 422

[liavyona]

Is your feature request related to a problem? Please describe.

Unlike definition of user or host with invalid restricted_to value in a policy, when asking for new host token with invalid CIDR value the output is a big and messy html with Error 500 Internal Server Error.

A clear and concise description of what the problem is. Ex. I would like to see [...] because [...].
I would like to get Error 422 Unprocessable Entitywhen sending invalid CIDR just like other requests acts.

Additional context