Update caliban-codegen-sbt to 2.8.1

Author: scala-steward

project/plugins.sbt

@@ -1,4 +1,4 @@
 addSbtPlugin("io.github.davidgregory084" % "sbt-tpolecat" % "0.1.20")
 addSbtPlugin("com.codecommit" % "sbt-github-actions" % "0.13.0")
-addSbtPlugin("com.github.ghostdogpr" % "caliban-codegen-sbt" % "1.1.1")
+addSbtPlugin("com.github.ghostdogpr" % "caliban-codegen-sbt" % "2.8.1")
 addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.5.12")