The annual gathering visits multiple U.S. cities and comes to Pittsburgh Aug. 23. Most days, if you walk by Allegheny Commons Park, you can observe a chess match, the farmer’s market, or even yoga. On Aug. 23, if you’re in proximity to Allegheny Commons Park during an event when Pittsburghers are being encouraged to come together, reflect, and make wishes, you could see Lake Elizabeth full of light at the Pittsburgh Water Lantern Festival…