remove two superfluous code lines

src/pystencils/backend/transformations/canonicalize_symbols.py

@@ -29,7 +29,6 @@ class CanonContext:
             self.live_symbols_map[symb] = symb
             return symb
         else:
-            self.encountered_symbols.add(symb)
             for i in count():
                 replacement_name = f"{symb.name}__{i}"
                 if self._ctx.find_symbol(replacement_name) is None:

src/pystencils/backend/transformations/hoist_loop_invariant_decls.py

@@ -73,8 +73,6 @@ class HoistLoopInvariantDeclarations:
     but makes no such assumption about instances of `CFunction`.
     """
 
-    #   TODO: Write unit tests
-
     def __init__(self, ctx: KernelCreationContext):
         self._ctx = ctx