Update manual-model.md

Author: ocots

docs/src/manual-model.md

@@ -58,7 +58,7 @@ We can now solve the problem (for more details, visit the [solve manual](@ref ma
 
 ```@example main
 using NLPModelsIpopt
-#solve(ocp)
+solve(ocp)
 nothing # hide
 ```
 
@@ -387,4 +387,4 @@ ocp = @def begin
     x(1) + 0.5∫( t + u(t)^2 ) → min     # explicit dependence on t
 end
 is_autonomous(ocp)
-```
+```