Update sbt-tpolecat to 0.1.20

Author: scala-steward

project/plugins.sbt

@@ -1,5 +1,5 @@
 addSbtPlugin("com.geirsson" % "sbt-ci-release" % "1.5.7")
-addSbtPlugin("io.github.davidgregory084" % "sbt-tpolecat" % "0.1.18")
+addSbtPlugin("io.github.davidgregory084" % "sbt-tpolecat" % "0.1.20")
 addSbtPlugin("com.codecommit" % "sbt-github-actions" % "0.10.1")
 addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.5.1")
 addSbtPlugin("org.portable-scala" % "sbt-scalajs-crossproject" % "1.0.0")