Update dependency org.scalameta:sbt-scalafmt to v2.5.4 (#161)

Author: renovate[bot]

project/plugins.sbt

@@ -17,7 +17,7 @@
 
 // https://scalameta.org/scalafmt/
 // https://github.com/scalameta/scalafmt
-addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.2")
+addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.4")
 
 // http://github.com/puffnfresh/wartremover
 addSbtPlugin("org.wartremover" % "sbt-wartremover" % "3.2.5")
@@ -37,7 +37,7 @@ addSbtPlugin("org.scoverage" % "sbt-scoverage" % "2.3.0")
 
 // Adds a `scalafmt` task for automatic source code formatting
 // https://scalameta.org/scalafmt/docs/installation.html
-addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.2")
+addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.4")
 
 // Adds a `dependencyUpdates` task to check Maven repositories for dependency updates
 // http://github.com/rtimush/sbt-updates