zeroconf: remove leftover camelcase identifier

eb9d0e828c30 (zeroconf: remove camelcase in identifiers, 2016-03-01)
forgot one occurrence of "numAuthorities", which makes test-paths.t
fail for me. I don't even know what zeroconf is, but this patch seems
obviously correct and it fixes the failing test case.

hgext/zeroconf/Zeroconf.py

@@ -555,7 +555,7 b' class DNSIncoming(object):'
         """Reads answers, authorities and additionals section of the packet"""
         format = '!HHiH'
         length = struct.calcsize(format)
-        n = self.numanswers + self.numAuthorities + self.numadditionals
+        n = self.numanswers + self.numauthorities + self.numadditionals
         for i in range(0, n):
             domain = self.readName()
             info = struct.unpack(format,