End-to-end test suite for Apache Iggy Web UI

As per [this Discord discussion](https://discordapp.com/channels/1144142576266530928/1144143410480038009/1454032941792493653) opening an issue to track work on the end-to-end tests for Web UI.

I am suggesting to use [`fantoccini`](https://crates.io/crates/fantoccini) with [`chromedriver`](https://developer.chrome.com/docs/chromedriver) to test Web UI. Example/reference of setup, utilities, and break-down
can be found [here](https://github.com/jonhoo/wewerewondering/tree/dda22908e4958992e09108e989bb868059d629ff/server/tests/e2e).

We can break the work into a few iterations for easier reviews:
- [ ] e2e tests setup (dependencies and utilities);
- [ ] test authentication (I think I might combine it with the first step, but let's see down the road)
- [ ] test main scenarios/pages (we can outline these later on)

The tests will be located under `iggy/core/server/tests`.

cc @spetz

Start by reading the example e2e setup and inspecting iggy/core/server/tests. Define the fantoccini and chromedriver setup and utilities first, then outline authentication and the main Web UI scenarios for review. Done means the setup is working and the authentication and agreed main-page flows have end-to-end coverage.

Written by the indexing model from the issue text.