Do not disable live migration by default

Live migration supposed to work in all qemu/kvm deployment.
It is expected switch to block magrate in case of no shared storage,
tempest expected to skip migration tests when there is no multiple
compute nodes and it would lead to test failure.
Also update the documentation regarding the options set by default.

Change-Id: Id9a25ad50df85f16f27a228a0075c2e073670937

config_tempest/main.py

@@ -102,8 +102,6 @@ def load_basic_defaults(conf):
             ("lock_path", "/tmp")
         ],
         "compute-feature-enabled": [
-            # Default deployment does not use shared storage
-            ("live_migration", "false"),
             ("preserve_ports", "true")
         ],
         "network-feature-enabled": [

doc/source/user/default.rst

@@ -24,10 +24,8 @@ Here is the list of tempest options, which are set by default:
     alt_project_name = alt_demo
 
     [auth]
-    ; if _member_ role is not present in the system, python-tempestconf
-    ; looks for member role and if the member is also not present
-    ; tempest_roles option is not set
-    tempest_roles = _member_
+    ; if member role is not present tempest_roles option is not set
+    tempest_roles = member
     admin_username = admin
     admin_project_name = admin
     admin_domain_name = Default
@@ -40,7 +38,6 @@ Here is the list of tempest options, which are set by default:
 
     [compute-feature-enabled]
     # Default deployment does not use shared storage
-    live_migration = false
     preserve_ports = true
 
     [network-feature-enabled]

releasenotes/notes/remove-default-setting-of-live_migration-8cfac9d7a6ad44a1.yaml

@@ -0,0 +1,8 @@
+---
+upgrade:
+  - |
+    The following option is no longer set by default
+
+    * ``CONF.compute-feature-enabled.live_migration false``
+
+    The default value for this option in Tempest is true.