GETting a filter requires auth (#1003)

api/client-server/filter.yaml

@@ -98,6 +98,8 @@ paths:
   "/user/{userId}/filter/{filterId}":
     get:
       summary: Download a filter
+      security:
+        - accessToken: []
       parameters:
         - in: path
           name: userId

changelogs/client_server.rst

@@ -75,6 +75,8 @@
   - Make ``m.notice`` description a bit harder in its phrasing to try to
     dissuade the same issues that occurred with IRC
     (`#750 <https://github.com/matrix-org/matrix-doc/pull/750>`_).
+  - ``GET /user/{userId}/filter/{filterId}`` requires authentication
+    (`#1003 <https://github.com/matrix-org/matrix-doc/pull/1003>`_).
 
 r0.2.0
 ======