Fix markup syntax in v2 state res (#1896)

Signed-off-by: Stuart Mumford <stuart@cadair.com>

changelogs/room_versions/newsfragments/1896.clarification.rst

@@ -0,0 +1 @@
+Fix a formatting issue in v2 state res.

content/rooms/fragments/v2-state-res.md

@@ -138,7 +138,7 @@ The *resolution* of a set of states is obtained as follows:
 1.  Select the set *X* of all *power events* that appear in the *full
     conflicted set*. For each such power event *P*, enlarge *X* by adding
     the events in the auth chain of *P* which also belong to the full
-    conflicted set. Sort $X$ into a list using the *reverse topological
+    conflicted set. Sort *X* into a list using the *reverse topological
     power ordering*.
 2.  Apply the *iterative auth checks algorithm*, starting from the
     *unconflicted state map*, to the list of events from the previous