make sql fixtures public

This patch makes the _StaticSqlFixture and _SqlFixture fixture classes
public by removing the leading underscore in the name. Based on
recent testing [1][2] the current versions of these fixtures seems to
work for consumers.

[1] https://review.opendev.org/#/c/657887/
[2] https://review.opendev.org/#/c/668000/

Change-Id: I5e9497d650176201407f0823f0fce46e009fb89c

neutron_lib/fixture.py

@@ -109,7 +109,7 @@ class _EnableSQLiteFKsFixture(fixtures.Fixture):
             self.addCleanup(disable_fks)
 
 
-class _SqlFixture(fixtures.Fixture):
+class SqlFixture(fixtures.Fixture):
 
     @classmethod
     def _generate_schema(cls, engine):
@@ -156,7 +156,7 @@ class _SqlFixture(fixtures.Fixture):
         self.useFixture(_EnableSQLiteFKsFixture(engine))
 
 
-class _StaticSqlFixture(_SqlFixture):
+class StaticSqlFixture(SqlFixture):
 
     _GLOBAL_RESOURCES = False
 

neutron_lib/tests/unit/db/_base.py

@@ -23,4 +23,4 @@ class SqlTestCase(base.BaseTestCase):
 
     def setUp(self):
         super(SqlTestCase, self).setUp()
-        self.useFixture(fixture._SqlFixture())
+        self.useFixture(fixture.SqlFixture())

neutron_lib/tests/unit/test_fixture.py

@@ -61,7 +61,7 @@ class SqlFixtureTestCase(base.BaseTestCase):
         options.set_defaults(
             cfg.CONF,
             connection='sqlite://')
-        self.fixture = fixture._StaticSqlFixture()
+        self.fixture = fixture.StaticSqlFixture()
         self.useFixture(self.fixture)
 
     def test_fixture(self):

releasenotes/notes/public-sql-fixtures-35d0aa74a368e217.yaml

@@ -0,0 +1,4 @@
+---
+features:
+  - The ``SqlFixture`` and ``StaticSqlFixture`` are now available in
+    ``neutron_lib.fixtures``.