Add update share type functional tests

Depends-on: I4c7bdd601d48b40c01639b5089d4bff259a7b3af
Part-of blueprint update-share-type-name-or-description

Change-Id: Id1073a964b6d034375b74fa89e3ebb39e2c56220
diff --git a/manila_tempest_tests/tests/api/base.py b/manila_tempest_tests/tests/api/base.py
index eca162a..3afd6fb 100644
--- a/manila_tempest_tests/tests/api/base.py
+++ b/manila_tempest_tests/tests/api/base.py
@@ -870,6 +870,16 @@
             cls.method_resources.insert(0, resource)
         return share_type
 
+    @classmethod
+    def update_share_type(cls, share_type_id, name=None,
+                          is_public=None, description=None,
+                          client=None):
+        if client is None:
+            client = cls.shares_v2_client
+        share_type = client.update_share_type(share_type_id, name,
+                                              is_public, description)
+        return share_type
+
     @staticmethod
     def add_extra_specs_to_dict(extra_specs=None):
         """Add any required extra-specs to share type dictionary"""