Do not replace 'th' with 's' and 'sch' with 'sz' in Polish

dictsource/pl_rules

@@ -646,7 +646,6 @@ _salce) son (_++   =sOn
         skj (A     S
 
 .group sc
-        sch        S
     pa) sch (a     sx
         sch (abA_  sx
         sch (ab_   sx
@@ -796,7 +795,6 @@ _anasta) si (L03_  sj
 .group	 th
     _e) th (anak   t
      _) the (_     dE
-        th         s
         th (ie_    s;
      _) th         t
      _) thank      fENk