[build] Update sbt-ci-release to 1.6.0

Author: scala-steward

project/plugins.sbt

@@ -1,6 +1,6 @@
 addSbtPlugin("ch.epfl.scala" % "sbt-tasty-mima" % "1.2.0")
 addSbtPlugin("com.eed3si9n" % "sbt-projectmatrix" % "0.10.0")
-addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.5.12")
+addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.6.0")
 addSbtPlugin("com.github.sbt" % "sbt-git" % "2.0.0")
 addSbtPlugin("com.typesafe" % "sbt-mima-plugin" % "1.1.3")
 addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.16.0")