Remove ambiguity for jsonb_path_match() and jsonb_path_exists()

Remove ambiguity for jsonb_path_match() and jsonb_path_exists()

There are 2-arguments and 4-arguments versions of jsonb_path_match() and
jsonb_path_exists().  But 4-arguments versions have optional 3rd and 4th
arguments, that leads to ambiguity.  In the same time 2-arguments versions are
needed only for @@ and @? operators.  So, rename 2-arguments versions to
remove the ambiguity.

Catversion is bumped.