Fix flaky playwright tests (#28959)

* Fix playwright flaky tests

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Wipe mailhog between test runs

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Delint

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

* Iterate

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

---------

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

playwright/testcontainers/mailhog.ts

@@ -0,0 +1,30 @@
+/*
+Copyright 2024 New Vector Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import { AbstractStartedContainer, GenericContainer, StartedTestContainer, Wait } from "testcontainers";
+import mailhog from "mailhog";
+
+export class MailhogContainer extends GenericContainer {
+    constructor() {
+        super("mailhog/mailhog:latest");
+
+        this.withExposedPorts(8025).withWaitStrategy(Wait.forListeningPorts());
+    }
+
+    public override async start(): Promise<StartedMailhogContainer> {
+        return new StartedMailhogContainer(await super.start());
+    }
+}
+
+export class StartedMailhogContainer extends AbstractStartedContainer {
+    public readonly client: mailhog.API;
+
+    constructor(container: StartedTestContainer) {
+        super(container);
+        this.client = mailhog({ host: container.getHost(), port: container.getMappedPort(8025) });
+    }
+}