The gambling boom is growing — and its next move could put poker chips in Marylanders’ pockets. Just over a year after online sports betting became legal in the state, two bills in the General Assembly seek to give voters the option to legalize internet gaming, which is gambling via online slot machines, blackjack, poker and other casino games. Lawmakers heard testimony earlier this week from proponents, including casino and industry leaders, and opponents, including those concerned about the effects of problem gambling and addiction.