What's behind MARA Holdings' big move? Here's what you need to know about the company's Bitcoin mining results in June.Shares of MARA Holdings (MARA -0.51%) soared 17.3% this week. The crypto-mining expert's stock rose 17.3% from last Friday's closing bell to the early market exit on Thursday, July 3, according to data from S&P Global Market Intelligence.Most of the price gain sprung from MARA's Bitcoin (BTC 0.30%) mining report, covering results in the month of June.Why block rewards matter to MARA Holding ...