fix an overindented line. not sure why our linters didn't catch this (#3123)

diff --git a/tests/test_x509.py b/tests/test_x509.py
index 47b81cb..e281579 100644
--- a/tests/test_x509.py
+++ b/tests/test_x509.py
@@ -3682,7 +3682,7 @@
 
     def test_iter_input(self):
         attrs = [
-                x509.NameAttribute(x509.ObjectIdentifier('2.999.1'), u'value1')
+            x509.NameAttribute(x509.ObjectIdentifier('2.999.1'), u'value1')
         ]
         name = x509.Name(iter(attrs))
         assert list(name) == attrs