ipatests: honor class inheritance in TestACMEwithExternalCA

TestACMEwithExternalCA subclasses TestACME which subclasses
CALessBase.

CALessBase is necessary to generate the certificates for the
test_third_party_certs() test.

This means that the TestACME install classmethod needs to be
called by its subclasses. But the install actually does the
installation of the servers as well so needs to be aborted
at that point in the case of a subclass.

https://pagure.io/freeipa/issue/8581

Signed-off-by: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Mohammad Rizwan <myusuf@redhat.com>
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>
Reviewed-By: Armando Neto <abiagion@redhat.com>

ipatests/test_integration/test_acme.py

@@ -109,6 +109,10 @@ class TestACME(CALessBase):
         # install packages before client install in case of IPA DNS problems
         cls.prepare_acme_client()
 
+        # Each subclass handles its own server installation procedure
+        if cls.__name__ != 'TestACME':
+            return
+
         tasks.install_master(cls.master, setup_dns=True)
 
         tasks.install_client(cls.master, cls.clients[0])
@@ -510,8 +514,7 @@ class TestACMEwithExternalCA(TestACME):
 
     @classmethod
     def install(cls, mh):
-
-        cls.prepare_acme_client()
+        super(TestACMEwithExternalCA, cls).install(mh)
 
         # install master with external-ca
         result = install_server_external_ca_step1(cls.master)