[FIX] web_timeline: order group_by field

Fix bug #2266: before this fix, the lines of the timeline view were always sorted by alphabetical order, ignoring the native order of the model on which the group_by field points to.

Fix duplicate entries in the 'fields' argument when the 'colors' parameters uses the same field in multiple conditions.

web_timeline/static/src/js/timeline_controller.js

@@ -66,6 +66,7 @@ odoo.define("web_timeline.TimelineController", function (require) {
                     kwargs: {
                         fields: fields,
                         domain: domains,
+                        order: [{name: this.renderer.arch.attrs.default_group_by}],
                     },
                     context: this.getSession().user_context,
                 }).then((data) =>