The exodus at Rockville Town Square continued this week when two neighboring businesses on Gibbs Street — Lab Cafe and Little Dipper Hot Pot House — closed their doors within days of each other. Lab Cafe, a bubble tea shop that opened in 2017, is the fifth business to fail at the same address since 2007. (Remember Bobby’s Crabcakes, Tippy’s Taco House, 82 Steak Out and Ev & Maddy’s?) Little Dipper also opened two years ago in the corner spot that once housed Noodles & Company. Add these two to the list of recent RTS closings that now includes Pandora Seafood House & Bar, Mellow Mushroom and LiquidBlue Denim Boutique, along with the neighboring Apollo restaurant. Dawson’s Market also closed last October, but it reopened in December under new ownership.