Update sbt-ci-release to 1.9.3 (#260)

Author: scala-steward

project/plugins.sbt

@@ -1,4 +1,4 @@
 addSbtPlugin("com.github.sbt" % "sbt-github-actions" % "0.25.0")
-addSbtPlugin("com.github.sbt" % "sbt-ci-release"     % "1.9.2")
+addSbtPlugin("com.github.sbt" % "sbt-ci-release"     % "1.9.3")
 addSbtPlugin("org.scalameta"  % "sbt-scalafmt"       % "2.5.4")
 addSbtPlugin("com.github.sbt" % "sbt-dynver"         % "5.1.0")