Merge pull request #219 from scala-steward/update/sbt-ci-release-1.9.3

Update sbt-ci-release to 1.9.3

Author: Johnnei

project/plugins.sbt

@@ -1,4 +1,4 @@
 resolvers += Classpaths.sbtPluginReleases
 
 addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.4")
-addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.9.2")
+addSbtPlugin("com.github.sbt" % "sbt-ci-release" % "1.9.3")