LONDON (Reuters) – Boris Johnson resigned as prime minister on Thursday, triggering a search for a new British leader. Below is how the process to find Johnson’s successor will work: \- Candidates putting themselves forward for the leadership, and there could be many, must be nominated by other Conservative lawmakers. How many nominations they require will be set out by the committee in charge of running the contest. In 2019 it was increased to eight nominations to speed up the process. \- Conservative lawmakers then hold several rounds of votes to whittle down the field. Each time they are as…