Removed test levels. Test levels are an invitation to inadvertently

not run tests.

src/ZEO/tests/InvalidationTests.py

@@ -236,8 +236,6 @@ class LargeUpdatesThread(FailableThread):
 
 class InvalidationTests:
 
-    level = 2
-
     # Minimum # of seconds the main thread lets the workers run.  The
     # test stops as soon as this much time has elapsed, and all threads
     # have managed to commit a change.

src/ZODB/tests/testFileStorage.py

@@ -334,8 +334,6 @@ class FileStorageNoRestoreRecoveryTest(FileStorageRecoveryTest):
 
 class SlowFileStorageTest(BaseFileStorageTests):
 
-    level = 2
-
     def check10Kstores(self):
         # The _get_cached_serial() method has a special case
         # every 8000 calls.  Make sure it gets minimal coverage.

src/ZODB/tests/testRecover.py

@@ -30,8 +30,6 @@ import transaction
 
 class RecoverTest(ZODB.tests.util.TestCase):
 
-    level = 2
-
     path = None
 
     def setUp(self):