Update sbt-mdoc to 2.5.3

Author: http4s-steward[bot]

project/plugins.sbt

@@ -9,6 +9,6 @@ libraryDependencies += "org.http4s" %% "http4s-ember-server" % http4sVersion
 
 addSbtPlugin("org.http4s" % "sbt-http4s-org" % "0.16.2")
 addSbtPlugin("com.armanbilge" % "sbt-bundlemon" % "0.1.4")
-addSbtPlugin("org.scalameta" % "sbt-mdoc" % "2.5.2")
+addSbtPlugin("org.scalameta" % "sbt-mdoc" % "2.5.3")
 addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.15.0")
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.11.0")