change(readme): remove lazy=false (#415)

`lazy=false` is a default value for lazy.nvim. Explicitly setting it is
redundant and leaves users confused. As a new user, I assumed
lazy-loading Comment.nvim would break the plugin, but that's not the
case.

Author: kuator

README.md

@@ -25,8 +25,7 @@
     'numToStr/Comment.nvim',
     opts = {
         -- add any options here
-    },
-    lazy = false,
+    }
 }
 
 ```