Adjusted index.md for documentation

Author: Liameloy

docs/src/index.md

@@ -122,5 +122,5 @@ makeisolevels(collect(0:0.1:10), 1, (1,-1),nothing)
 ## Private API
 
 ```@docs
-GridVisualizeTools.tet_x_plane!
+GridVisualizeTools.calculate_plane_tetrahedron_intersection!
 ```