Merge pull request #187 from scala-steward/update/sbt-header-5.1.0

Update sbt-header to 5.1.0

Author: SethTisue

project/plugins.sbt

@@ -6,4 +6,4 @@ addSbtPlugin("org.scala-lang.modules" % "sbt-scala-module"         % "2.0.0")
 addSbtPlugin("ch.epfl.scala"          % "sbt-scalafix"             % "0.9.4")
 addSbtPlugin("com.eed3si9n"           % "sbt-buildinfo"            % "0.7.0")
 addSbtPlugin("com.jsuereth"           % "sbt-pgp"                  % "1.1.2-1")
-addSbtPlugin("de.heikoseeberger"      % "sbt-header"               % "5.0.0")
+addSbtPlugin("de.heikoseeberger"      % "sbt-header"               % "5.1.0")