Update sbt-scalafmt to 2.5.5 (#893)

Author: scala-steward

project/plugins.sbt

@@ -5,7 +5,7 @@ addSbtPlugin("com.github.sbt" % "sbt-pgp"      % "2.3.1")
 //addSbtPlugin("com.github.sbt"   % "sbt-jacoco"      % "3.3.0")
 addSbtPlugin("org.xerial.sbt"   % "sbt-jcheckstyle" % "0.2.1")
 addSbtPlugin("com.github.sbt" % "sbt-osgi"        % "0.10.0")
-addSbtPlugin("org.scalameta"    % "sbt-scalafmt"    % "2.5.4")
+addSbtPlugin("org.scalameta"    % "sbt-scalafmt"    % "2.5.5")
 addSbtPlugin("com.github.sbt"     % "sbt-dynver"      % "5.1.0")
 
 scalacOptions ++= Seq("-deprecation", "-feature")