DEV: remove do-not-disturb widget (#26156)

It seems like this is a legacy widget which was used here f899652422/app/assets/javascripts/discourse/app/widgets/quick-access-panel.js (L106) but usage got removed in https://github.com/discourse/discourse/pull/21308/files#diff-9f7a1e3cde1ef93d38ba40ebf295749fb217eee81b95e95c34f98721274cdca9 and the widget didn't get removed.

app/assets/javascripts/discourse/app/widgets/do-not-disturb.js

@@ -1,54 +0,0 @@
-import { h } from "virtual-dom";
-import DoNotDisturbModal from "discourse/components/modal/do-not-disturb";
-import { dateNode } from "discourse/helpers/node";
-import DoNotDisturb from "discourse/lib/do-not-disturb";
-import { createWidget } from "discourse/widgets/widget";
-import { iconNode } from "discourse-common/lib/icon-library";
-import I18n from "discourse-i18n";
-
-export default createWidget("do-not-disturb", {
-  tagName: "li.do-not-disturb",
-  services: ["modal"],
-
-  saving: false,
-
-  html() {
-    const isOn = this.currentUser.isInDoNotDisturb();
-    return [this._menuButton(isOn)];
-  },
-
-  click() {
-    if (this.saving) {
-      return;
-    }
-
-    this.saving = true;
-    if (this.currentUser.do_not_disturb_until) {
-      return this.currentUser.leaveDoNotDisturb().then(() => {
-        this.saving = false;
-      });
-    } else {
-      this.saving = false;
-      return this.modal.show(DoNotDisturbModal);
-    }
-  },
-
-  _menuButton(isOn) {
-    const icon = iconNode(isOn ? "toggle-on" : "toggle-off");
-    return h("button.btn-flat.do-not-disturb-inner-container", [
-      icon,
-      this._label(),
-    ]);
-  },
-
-  _label() {
-    const content = [h("span", I18n.t("pause_notifications.label"))];
-
-    const until = this.currentUser.do_not_disturb_until;
-    if (!DoNotDisturb.isEternal(until)) {
-      content.push(dateNode(until));
-    }
-
-    return h("span.do-not-disturb-label", content);
-  },
-});