Background

The Synthetics Agent currently has a fixed/global timeout defined which cannot be changed by the user (and them changing Playwright configurations manually may cause problems). We need a mechanism that is documented and exposed to the user on how they can set these timeouts for individual steps, or globally at the user journey level (which apply to all of the steps).

User Story

As a user of Elastic Synthetics
I want to be able to configure user journey and step timeouts for Synthetic monitors
So that I can control exactly how much time each step should wait based on how long I reasonably expect the interactions of that step to take (e.g. an AJAX request to populate a drop down will typically take less time than a full page load)