Update jackson2 version to 2.21.0 (#216)

Author: pjfanning

build.sbt

@@ -303,7 +303,7 @@ lazy val library =
       val argonaut      = "6.3.11"
       val avro4s        = "4.1.2"
       val circe         = "0.14.15"
-      val jackson2      = "2.20.1"
+      val jackson2      = "2.21.0"
       val jackson3      = "3.0.3"
       val json4s        = "4.1.0"
       val jsoniterScala = "2.38.8"