update servant-server CHANGELOG.md

Author: Philonous

servant-server/CHANGELOG.md

@@ -3,6 +3,10 @@
 
 * Add `err422` Unprocessable Entity
   ([#646](https://github.com/haskell-servant/servant/pull/646))
+* Changed `HasServer` instances for `QueryParam` and `QueryParam` to throw 400
+  when parsing fails
+  ([#649](6e77453b67dc164e5381fb867e5e6475302619a3))
+* Added `paramD` block to `Delayed`
 
 * `Handler` is now an abstract datatype. Migration hint: change `throwE` to `throwError`.
   ([#641](https://github.com/haskell-servant/servant/issues/641))