tests: Remove unused .css = noop.

The front end tests pass without these removed lines. There are a few
such lines that are still necessary.

web/tests/composebox_typeahead.test.cjs

@@ -1718,7 +1718,6 @@ test("initialize", ({override, override_rewire, mock_template}) => {
     $("form#send_message_form").off("keydown");
     $("form#send_message_form").off("keyup");
     $("#private_message_recipient").off("blur");
-    $("#send_later").css = noop;
     ct.initialize({
         on_enter_send: finish,
     });

web/tests/popover_menus_data.test.cjs

@@ -153,8 +153,6 @@ function set_page_params_no_edit_restrictions({override}) {
 function test(label, f) {
     run_test(label, (helpers) => {
         // Stubs for calculate_timestamp_widths()
-        $("<div>").css = noop;
-        $(":root").css = noop;
         $("<div>").width = noop;
         $("<div>").remove = noop;
 

web/tests/upload.test.cjs

@@ -141,7 +141,6 @@ test("config", () => {
 });
 
 test("show_error_message", ({mock_template}) => {
-    $("#compose_banners .upload_banner .moving_bar").css = noop;
     $("#compose_banners .upload_banner").length = 0;
 
     let banner_shown = false;
@@ -167,7 +166,6 @@ test("show_error_message", ({mock_template}) => {
 
 test("upload_files", async ({mock_template, override, override_rewire}) => {
     $("#compose_banners .upload_banner").remove = noop;
-    $("#compose_banners .upload_banner .moving_bar").css = noop;
     $("#compose_banners .upload_banner").length = 0;
 
     let files = [
@@ -447,7 +445,6 @@ test("copy_paste", ({override, override_rewire}) => {
 });
 
 test("uppy_events", ({override_rewire, mock_template}) => {
-    $("#compose_banners .upload_banner .moving_bar").css = noop;
     $("#compose_banners .upload_banner").length = 0;
     override_rewire(compose_ui, "smart_insert_inline", noop);
     override_rewire(compose_validate, "validate_and_update_send_button_status", noop);

web/tests/user_events.test.cjs

@@ -5,7 +5,6 @@ const assert = require("node:assert/strict");
 const {mock_esm, zrequire} = require("./lib/namespace.cjs");
 const {run_test, noop} = require("./lib/test.cjs");
 const blueslip = require("./lib/zblueslip.cjs");
-const $ = require("./lib/zjquery.cjs");
 
 const message_live_update = mock_esm("../src/message_live_update");
 const navbar_alerts = mock_esm("../src/navbar_alerts");
@@ -223,8 +222,6 @@ run_test("updates", ({override}) => {
     assert.equal(user_id, isaac.user_id);
     assert.equal(person.avatar_url, avatar_url);
 
-    $("#personal-menu .header-button-avatar").css = noop;
-
     user_events.update_person({user_id: me.user_id, avatar_url: "http://gravatar.com/789456"});
     person = people.get_by_email(me.email);
     assert.equal(person.full_name, "Me V2");