.github/workflows: add webclient workflow

Add workflow to run yarn lint/test/format-check against the web
client on pull requests.

Updates #10261

Signed-off-by: Sonia Appasamy <sonia@tailscale.com>

client/web/src/utils/util.test.ts

@@ -0,0 +1,21 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+import { isTailscaleIPv6, pluralize } from "src/utils/util"
+import { describe, expect, it } from "vitest"
+
+describe("pluralize", () => {
+  it("test routes", () => {
+    expect(pluralize("route", "routes", 1)).toBe("route")
+    expect(pluralize("route", "routes", 2)).toBe("routes")
+  })
+})
+
+describe("isTailscaleIPv6", () => {
+  it("test ips", () => {
+    expect(isTailscaleIPv6("100.101.102.103")).toBeFalsy()
+    expect(
+      isTailscaleIPv6("fd7a:115c:a1e0:ab11:1111:cd11:111e:f11g")
+    ).toBeTruthy()
+  })
+})