A travel insurance document is not required for a standard UK visitor visa. However, I recommend that all passengers purchase travel health insurance while traveling by road. This could be medical emergencies or medical emergencies that add up to the travel amount.
You choose to purchase health insurance with the expectation that it will cover your needs and approximate developmental prospects, including length and time of visit. Also make sure that you have all the necessary documents for receiving medical care abroad, including the contact information of the insurance company and details of your insurance.