Can't update CA certificate for existing oVirt compute resource
When an oVirt CR is created, it saves public key of CA that issues the certificate for oVirt in attrs[:public_key]. In 1.7.0 there was added a new text-area so user can set the CA cert manually in the form. There's also public_key hidden field that was used before to keep public_key on updates if there was already some data center loaded. Since it's after the text area, it always overrides its value which is a problem when editing the CR.
Steps to reproduce:
1. create oVirt CR, make sure it has public key stored
2. change the CA/self-signed certificate on oVirt instance
3. edit the CR in Foreman, delete old public key in text area and try hitting load datacenters/test connection button
you'll see that the request fails on SSL issue, if you check the text area, you can see that the public key is reset to the old value
it should load new public key and sucessfuly load data centers