Update sbt-scalafmt to 2.3.1

[scala-steward]

Updates org.scalameta:sbt-scalafmt from 2.3.0 to 2.3.1.
Release Notes/Changelog

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.

Have a fantastic day writing Scala!

Ignore 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" } ]

labels: sbt-plugin-update, semver-patch

[codecov]

Codecov Report

Merging #917 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #917   +/-   ##
=======================================
  Coverage   80.54%   80.54%           
=======================================
  Files         248      248           
  Lines        9548     9548           
  Branches      665      665           
=======================================
  Hits         7690     7690           
  Misses       1858     1858

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