Update sbt-ci-release to 1.9.3

Author: scala-steward

project/plugins.sbt

@@ -1,3 +1,3 @@
 addSbtPlugin("pl.project13.scala" % "sbt-jmh" % "0.4.7")
 addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.5")
-addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.9.2")
+addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.9.3")