Donald Trump has said he knows who his vice presidential pick will be but refused to name them outright. The 78-year-old has so far remained tight-lipped about who could fill the coveted position with reports suggesting three people are in the running for the role. However, Trump, who recently became the first former president to become convicted of a crime, has broken his silence with a major hint at when he could unveil the candidate. When asked whether he has decided on his pick for VP during a campaign stop in Philadelphia, Trump hinted that although he has a pick, “nobody knows” his choic…