remove unnecessary sys.path manipulation in tests

tests/queryset/field_list.py

@@ -1,6 +1,3 @@
-import sys
-sys.path[0:0] = [""]
-
 import unittest
 
 from mongoengine import *

tests/queryset/geo.py

@@ -1,9 +1,5 @@
-import sys
-
-sys.path[0:0] = [""]
-
-import unittest
 from datetime import datetime, timedelta
+import unittest
 
 from pymongo.errors import OperationFailure
 from mongoengine import *

tests/queryset/modify.py

@@ -1,6 +1,3 @@
-import sys
-sys.path[0:0] = [""]
-
 import unittest
 
 from mongoengine import connect, Document, IntField
@@ -99,4 +96,4 @@ class FindAndModifyTest(unittest.TestCase):
 
 
 if __name__ == '__main__':
-    unittest.main()
+    unittest.main()