instance.gen task: make example instance name less confusing

See pleroma/pleroma!2245 (comment 52217)

lib/mix/tasks/pleroma/instance.ex

@@ -65,7 +65,7 @@ def run(["gen" | rest]) do
         get_option(
           options,
           :instance_name,
-          "What is the name of your instance? (e.g. Pleroma/Soykaf)",
+          "What is the name of your instance? (e.g. The Corndog Emporium)",
           domain
         )