fixes #10234 - Fix NIC taxonomies validation tests

Some of the tests in #9391 changed the way subnets should work regarding
taxonomies and some test data, this commit fixes that so tests are green
once again.

Fixes #9391 - Added validation code to NIC, so it validates that host's location/org is compatible with the one set on NIC's subnet

fixes #10020 - add next-server/filename attrs to provision NIC DHCP record

A host's DHCP record used to be constructed with PXE attributes in
Orchestration::DHCP, but moved to Nic::Managed during 43c4bd7. Nic::Managed
didn't add PXE attributes, so this commit adds these when provision? is set....

Fixes #10123 - Tests API v2 external user groups

The addition of a .refresh call after create, update and delete, caused
our tests to fail because of many failed calls to LDAP.
We can just expect the method to return true as we're not testing the
refresh functionality in these methods.

Fixes #10093 - VMware#create_vm calls clone_vm

Apply '.with_indifferent_access' to the args passed in to create_vm,
ensuring symbol test for args[:image_id] succeeds when args["image_id"]
is present.

fixes #9993 - Removes root password and partition table reqs unless build mode selected

Fixes #9884 - refresh deleted external usergroups

Fixes #9947 - restrict user taxonomies if none is set

Fixes #7615 - filter ignore current context

Fixes #9362 - Corrected CoreOS mediapath