hs-v3: Add changes file for 28026

Signed-off-by: David Goulet <dgoulet@torproject.org>

changes/ticket28026

@@ -0,0 +1,3 @@
+  o Documentation (hidden service manpage):
+    - Improve HSv3 client authorization by making some options more explicit
+      and detailed. Closes ticket 28026. Patch by "mtigas".