Update django-statsd-mozilla from 0.3.16 to 0.4.0

requirements/prod.txt

@@ -231,8 +231,9 @@ django-post-request-task==0.1.1 \
 django-session-csrf==0.7.1 \
     --hash=sha256:e17177e6e2e6518ec7ce6693ad10a5c747f8571d09f4cfa9082599334421605d \
     --hash=sha256:ff8c10e30d312c77fc6a6db7710e22b9383e28c03b7fe958876ca96f39aa6cf2
-django-statsd-mozilla==0.3.16 \
-    --hash=sha256:925f0f13e5a1e7863e5ed1179fd0f6f1a519e5a0293714ba76745286aad7ed02
+django-statsd-mozilla==0.4.0 \
+    --hash=sha256:81084f3d426f5184f0a0f1dbfe035cc26b66f041d2184559d916a228d856f0d3 \
+    --hash=sha256:0d87cb63de8107279cbb748caad9aa74c6a44e7e96ccc5dbf07b89f77285a4b8
 django-tables2==1.10.0 \
     --hash=sha256:51607a1dada9ad10cf09aaadc7208960c6922ab720dd8b5d0c0d1b2222f00a66
 django-waffle==0.12.0 \