Fix a spelling typo in tempest/thirdparty/boto/test.py

s/attching/attching

Change-Id: Idfdc5b6be3f82468c62217d893b9d37c74f6d994
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
diff --git a/tempest/thirdparty/boto/test.py b/tempest/thirdparty/boto/test.py
index 1ff4dee..9f119b4 100644
--- a/tempest/thirdparty/boto/test.py
+++ b/tempest/thirdparty/boto/test.py
@@ -505,7 +505,7 @@
             LOG.critical("%s Volume has %s snapshot(s)", volume.id,
                          map(snaps.id, snaps))
 
-        # NOTE(afazekas): detaching/attching not valid EC2 status
+        # NOTE(afazekas): detaching/attaching not valid EC2 status
         def _volume_state():
             volume.update(validate=True)
             try: