doc: fix debugging-isis reference

Debugging-isis tag was moved.

Move it to right place.

Fixes: 9389175 ("doc: add documentation for IS-IS Segment Routing")
Signed-off-by: Louis Scalbert <louis.scalbert@6wind.com>

doc/user/isisd.rst

@@ -368,8 +368,7 @@ Traffic Engineering
 
    :ref:`ospf-traffic-engineering`
 
-
-.. _debugging-isis:
+.. _isis-segment-routing:
 
 Segment Routing
 ===============
@@ -415,6 +414,8 @@ Known limitations:
 
    Show detailed information about all learned Segment Routing Nodes.
 
+.. _debugging-isis:
+
 Debugging ISIS
 ==============