The new UK prime minister to replace the outgoing Boris Johnson will be announced on September 5, the ruling Conservative party said on Monday, with 11 hopefuls currently vying for the job. The leadership contest was triggered last week when Johnson, 58, was forced to step down after a frenzy of more than 50 resignations from his government, in opposition to his scandal-hit premiership. The influential 1922 Committee of non-ministerial Tory MPs in parliament on Monday outlined a timetable for the party’s leadership election. Nominations will officially open and close on Tuesday, with a new pri…