Update sbt-header to 5.4.0

[scala-steward]

Updates de.heikoseeberger:sbt-header from 5.3.1 to 5.4.0.

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 = "de.heikoseeberger", artifactId = "sbt-header" } ]

labels: sbt-plugin-update, semver-minor

[codecov]

Codecov Report

Merging #296 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #296   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files          13     13           
  Lines         397    397           
  Branches       18     18           
=====================================
  Hits          397    397

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 40ecefd...e9fb104. Read the comment docs.