test_ipagetkeytab: test retrieval of explicit encryption types
In order to test a fix for https://pagure.io/freeipa/issue/7953,
we need to create a keytab with a particular encryption type
(arcfour-hmac) and attempt to request generation of ipaNTHash attribute
from Kerberos keys in LDAP.
Add a test case that performs this operation.
Related: https://pagure.io/freeipa/issue/7953
Reviewed-By: Christian Heimes <cheimes@redhat.com>