scatter3d errorbars update baselines

gl3d_errobars_zx.json had to be updated because thickness is defined per axis instead of previously being determined by the thickness of error_z

Author: antoinerg

Diff for: test/image/baselines/gl3d_errorbars_xy.png

@@ -35,7 +35,8 @@
             "error_x": {
                 "type": "constant",
                 "value": 0.1,
-                "color": "black"
+                "color": "black",
+                "thickness": 10
             },
             "marker": {
                 "symbol": "square"