fix ignore unit test regex

.pylintrc

@@ -52,7 +52,7 @@ ignore=CVS,tests.py
 # ignore-list. The regex matches against paths and can be in Posix or Windows
 # format. Because '\\' represents the directory delimiter on Windows systems,
 # it can't be used as an escape character.
-ignore-paths=^.*migrations/.*$,^.*_tests/.*$,^.*_unit_test.*$
+ignore-paths=^.*migrations/.*$,^.*_tests/.*$,^.*unit_test.*$
 
 # Files or directories matching the regular expression patterns are skipped.
 # The regex matches against base names, not paths. The default value ignores