Update snakeyaml-engine to 2.8

Author: scala-steward

build.sbt

@@ -11,7 +11,7 @@ val Versions = new {
   val scalaTest = "3.2.18"
   val scalaTestPlus = "3.2.18.0"
   val snakeYaml = "2.2"
-  val snakeYamlEngine = "2.7"
+  val snakeYamlEngine = "2.8"
   val previousCirceYamls = Set("0.14.0", "0.14.1", "0.14.2")
 
   val scala213 = "2.13.14"