Add sbt io to the sbt project

Without this, the sbt io version is used by the compiler which means
that apis added in later versions of io are not available. I don't
understand why the transitive dependency on io is not used, but this
fixes the issue.

build.sbt

@@ -648,7 +648,7 @@ lazy val sbtProj = (project in file("sbt"))
     Test / run / outputStrategy := Some(StdoutOutput),
     Test / run / fork := true,
   )
-  .configure(addSbtCompilerBridge)
+  .configure(addSbtIO, addSbtCompilerBridge)
 
 lazy val sbtBig = (project in file(".big"))
   .dependsOn(sbtProj)