move pymemcache args test to pymemcache-specific fixture

this was failing on a generic tox run due to dependencies

Change-Id: I25806a256e6e5f876a1c896e6a76bec976612cef

Author: zzzeek

tests/cache/test_memcached_backend.py

@@ -171,6 +171,20 @@ class BMemcachedSerializerTest(
 class PyMemcacheTest(_NonDistributedMemcachedTest):
     backend = "dogpile.cache.pymemcache"
 
+    def test_pymemcache_enable_retry_client_not_set(self):
+        with mock.patch("warnings.warn") as warn_mock:
+            _ = make_region().configure(
+                "dogpile.cache.pymemcache",
+                arguments={"url": "foo", "retry_attempts": 2},
+            )
+            eq_(
+                warn_mock.mock_calls[0],
+                mock.call(
+                    "enable_retry_client is not set; retry options "
+                    "will be ignored"
+                ),
+            )
+
 
 class PyMemcacheDistributedWithTimeoutTest(
     _DistributedMemcachedWithTimeoutTest
@@ -340,20 +354,6 @@ def test_set_min_compress_len(self):
         backend.set("foo", "bar")
         eq_(backend._clients.memcached.canary, [{"min_compress_len": 20}])
 
-    def test_pymemcache_enable_retry_client_not_set(self):
-        with mock.patch("warnings.warn") as warn_mock:
-            _ = make_region().configure(
-                "dogpile.cache.pymemcache",
-                arguments={"url": "foo", "retry_attempts": 2},
-            )
-            eq_(
-                warn_mock.mock_calls[0],
-                mock.call(
-                    "enable_retry_client is not set; retry options "
-                    "will be ignored"
-                ),
-            )
-
 
 class LocalThreadTest(TestCase):
     def setUp(self):