Update sbt-scalafmt to 2.5.6

[gvolpe]

About this PR

📦 Updates org.scalameta:sbt-scalafmt from 2.5.5 to 2.5.6

📜 GitHub Release Notes - Version Diff

Usage

✅ Please merge!

I'll automatically update this PR to resolve conflicts as long as you don't change it yourself.

If you'd like to skip this version, you can just close this PR. If you have any feedback, just mention me in the comments below.

Configure Scala Steward for your repository with a .scala-steward.conf file.

Have a fantastic day writing Scala!

⚙ Adjust future updates

Add this to your .scala-steward.conf file to ignore future updates of this dependency:

updates.ignore = [ { groupId = "org.scalameta", artifactId = "sbt-scalafmt" } ]

Or, add this to slow down future updates of this dependency:

dependencyOverrides = [{
  pullRequests = { frequency = "30 days" },
  dependency = { groupId = "org.scalameta", artifactId = "sbt-scalafmt" }
}]

^{labels: sbt-plugin-update, early-semver-patch, semver-spec-patch, commit-count:1}

[froth]

@gvolpe I fixed this pr by ThisBuild / libraryDependencySchemes += "org.scala-lang.modules" %% "scala-xml" % VersionScheme.Always. Problem is that sbt-microsite uses an old java-xml version and is no longer maintained. This fixes it for now but a medium term solution would be to migrate away from sbt-microsite. At the moment I lack time and motivation to do that, so this is the easiest solution for now.