Delete extraneous comma

Author: mlimber

_posts/2018-02-15-totw-142.md

@@ -89,7 +89,7 @@ There could be many semantically different types that can be constructed
 from `{server, connection}`, such as a `Response` going in the opposite 
 direction from a `Request`. 
 
-Such a constructor should be `explicit`, so that we can’t pass 
+Such a constructor should be `explicit` so that we can’t pass 
 `{server, connection}` to a function that accepts a `Request` or 
 `Response` parameter. Marking the constructor as `explicit` makes the 
 code clearer for readers by requiring the target type (and thus the