Update sbt-sonatype to 3.9.9

Author: foundweekends-bot[bot]

project/plugins.sbt

@@ -1,5 +1,5 @@
 addSbtPlugin("com.github.sbt" % "sbt-pgp" % "2.1.2")
-addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "3.9.7")
+addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "3.9.9")
 addSbtPlugin("com.github.sbt" % "sbt-release" % "1.1.0")
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.10.0")
 addSbtPlugin("com.github.xuwei-k" % "sbt-proguard" % "0.5.0")