Integration: swatch references bump the story revision with wrapping_add

#456 makes every story revision increment wrap; next's swatch_refs.rs (added after the PR's base) still used rev += 1.

crates/doc/src/swatch_refs.rs

@@ -137,7 +137,7 @@ impl Names<'_> {
         for t in st.tables.values_mut() {
             self.table(Arc::make_mut(t));
         }
-        st.rev += 1;
+        st.rev = st.rev.wrapping_add(1);
     }
 }