Update docstrin of flux_nonconservative_powell_local_symmetric

Co-authored-by: Michael Schlottke-Lakemper <[email protected]>

src/equations/ideal_glm_mhd_2d.jl

@@ -295,7 +295,7 @@ of local and symmetric parts. It is equivalent to the non-conservative flux of B
 et al. (`flux_nonconservative_powell`) for conforming meshes but it yields different
 results on non-conforming meshes(!).
 
-The two functions below, which share the same name, return yield either the local 
+The two other flux functions with the same name return either the local 
 or symmetric portion of the non-conservative flux based on the type of the 
 nonconservative_type argument, employing multiple dispatch. They are used to
 compute the subcell fluxes in dg_2d_subcell_limiters.jl.