Replace abc.abstractproperty with property and abc.abstractmethod

Replace abc.abstractproperty with property and abc.abstractmethod,
as abc.abstractproperty has been deprecated since python3.3[1]

[1]https://docs.python.org/3.8/whatsnew/3.3.html?highlight=deprecated#abc

Change-Id: Id90fbd2c53fd49341043bde740500a857a4339d3

oslo_db/sqlalchemy/test_migrations.py

@@ -77,7 +77,8 @@ class WalkVersionsMixin(object, metaclass=abc.ABCMeta):
 
     """
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def INIT_VERSION(self):
         """Initial version of a migration repository.
 
@@ -87,7 +88,8 @@ class WalkVersionsMixin(object, metaclass=abc.ABCMeta):
         """
         pass
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def REPOSITORY(self):
         """Allows basic manipulation with migration repository.
 
@@ -95,7 +97,8 @@ class WalkVersionsMixin(object, metaclass=abc.ABCMeta):
         """
         pass
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def migration_api(self):
         """Provides API for upgrading, downgrading and version manipulations.
 
@@ -103,7 +106,8 @@ class WalkVersionsMixin(object, metaclass=abc.ABCMeta):
         """
         pass
 
-    @abc.abstractproperty
+    @property
+    @abc.abstractmethod
     def migrate_engine(self):
         """Provides engine instance.