trivial: whitespace

I ran emacs's "M-x whitespace-cleanup" on the files that Toby's recent patch had touched that had trailing whitespace on some lines.

src/allmydata/test/test_ambient_upload_authority.py

@@ -94,4 +94,3 @@ class TestAmbientUploadAuthorityDisabled(TestCase):
 
     def test_ambient_upload_authority_disabled(self):
         return self._test_ambient_upload_authority()
-

src/allmydata/web/root.py

@@ -1,4 +1,3 @@
-
 import time
 
 from twisted.internet import address

src/allmydata/webish.py

@@ -1,4 +1,3 @@
-
 import time
 from twisted.application import service, strports, internet
 from twisted.web import http