Connecticut’s third reopening phase during the coronavirus pandemic is getting a less-than-enthusiastic response from some business owners and arts venues. The state on Thursday will increase capacity limits at a number of businesses ranging from restaurants to indoor and outdoor performing arts venues. But many restaurant owners say they won’t be able to reach the new 75 percent capacity limit for indoor dining because they don’t have the space under the 6-foot social distancing requirement. Many theaters and concert venues are not opening this week, saying shows already have been canceled and they can’t make money with half-full facilities.