GPencil: Change Paint cursor to DOT

After doing some test, the cross cursor is too intrusive when you are drawing in grease pencil, so we decided to change by Dot cursor.

Reviewers: @brecht @mendio @pepeland @pablovazquez @billreynish

release/scripts/startup/bl_ui/space_toolsystem_toolbar.py

@@ -1320,7 +1320,7 @@ class _defs_gpencil_paint:
             icon_prefix="brush.gpencil_draw.",
             type=bpy.types.Brush,
             attr="gpencil_tool",
-            cursor='PAINT_CROSS',
+            cursor='DOT',
             tooldef_keywords=dict(
                 operator="gpencil.draw",
             ),