Improve formatting of inline code in Sets.rst

Author: mfripp

doc/OnlineDocs/pyomo_modeling_components/Sets.rst

@@ -452,7 +452,7 @@ for this model, a toy data file (in AMPL "``.dat``" format) would be:
    >>> inst = model.create_instance('src/scripting/Isinglecomm.dat')
 
 This can also be done much more efficiently using initialization functions
-that accept only a model block and return a `dict` with all the information
+that accept only a model block and return a ``dict`` with all the information
 needed for the indexed set:
 
 .. doctest::