Fix scala 3 warning. remove redundant final

```
[error] 122 |final object RunConfig {
[error]     |^^^^^
[error]     |Modifier final is redundant for this definition
```

Author: xuwei-k

js-envs/src/main/scala/org/scalajs/jsenv/RunConfig.scala

@@ -119,7 +119,7 @@ final class RunConfig private (
   }
 }
 
-final object RunConfig {
+object RunConfig {
   type OnOutputStream = (Option[InputStream], Option[InputStream]) => Unit
   def apply(): RunConfig = new RunConfig()
 

nodejs-env/src/main/scala/org/scalajs/jsenv/nodejs/ComSupport.scala

@@ -235,7 +235,7 @@ object ComRun {
       jvm2js: DataOutputStream,
       js2jvm: DataInputStream) extends State
 
-  private final case object Closing extends State
+  private case object Closing extends State
 
   private def writeMsg(s: DataOutputStream, msg: String): Unit = {
     s.writeInt(msg.length)