Update scala-library to 2.13.18 in series/0.24

Author: http4s-steward[bot]

build.sbt

@@ -10,7 +10,7 @@ ThisBuild / developers := List(
 // publish website from this branch
 ThisBuild / tlSitePublishBranch := Some("main")
 
-val Scala213 = "2.13.16"
+val Scala213 = "2.13.18"
 ThisBuild / crossScalaVersions := Seq("2.12.20", Scala213, "3.3.7")
 ThisBuild / scalaVersion := Scala213 // the default Scala