Update src/solvers/dgsem_structured/dg_3d.jl

Co-authored-by: Andrew Winters <[email protected]>

src/solvers/dgsem_structured/dg_3d.jl

@@ -53,7 +53,7 @@ end
 `weak_form_kernel!` is only implemented for conserved terms as 
 non-conservative terms should always be discretized in conjunction with a flux-splitting scheme, 
 see `flux_differencing_kernel!`.
-This treatment is required to achieve e.g. entropy-stability and well-balancedness.
+This treatment is required to achieve, e.g., entropy-stability or well-balancedness.
 See also https://github.com/trixi-framework/Trixi.jl/issues/1671#issuecomment-1765644064
 =#
 @inline function weak_form_kernel!(du, u,