fix docs

Author: danieldouglas92

cookbooks/2D_subduction_with_two_phase_flow/doc/2D_subduction_two_phase_flow.md

@@ -45,7 +45,7 @@ In these models, the water density (1000 kg/m$^3$) is significantly lower than t
 ```
 
 ```{figure-md} fig:viscosity-comparison
-<img src="viscosity_profile.png" />
+<img src="viscosity_profiles.png" />
 
  The viscosity of the model within the immediate vicinity of the subduction zone. The vectors show the direction of and are scaled by the velocity of the solid phase.
 ```