Update http4s-blaze-client, http4s-circe, ... to 0.21.16

Author: 47erbot

project/ProjectPlugin.scala

@@ -17,7 +17,7 @@ object ProjectPlugin extends AutoPlugin {
       val base64: String    = "0.3.0"
       val cats: String      = "2.3.1"
       val circe: String     = "0.13.0"
-      val http4s: String    = "0.21.15"
+      val http4s: String    = "0.21.16"
       val paradise: String  = "2.1.1"
       val scalamock: String = "5.1.0"
       val scalatest: String = "3.2.3"