Update bump script following libraries.toml changes

Author: BoD

scripts/bump-kotlin-nightlies.main.kts

@@ -26,7 +26,6 @@ fun bumpVersions() {
     file.writeText(
         file.readText()
             .replaceVersion("kotlin-plugin", kotlinVersion)
-            .replaceVersion("kotlin-plugin-max", kotlinVersion)
             .replaceVersion("ksp", kspVersion)
     )
   }
@@ -77,7 +76,9 @@ fun getLatestVersion(url: String, prefix: String? = null): String {
 
 fun runCommand(vararg args: String): String {
   println("Running command: '${args.joinToString(" ")}'")
-  val builder = ProcessBuilder(*args).redirectError(ProcessBuilder.Redirect.INHERIT)
+  val builder = ProcessBuilder(*args)
+      .redirectErrorStream(true)
+      .redirectError(ProcessBuilder.Redirect.INHERIT)
   val process = builder.start()
   val output = StringBuilder()
   while (true) {
@@ -87,7 +88,7 @@ fun runCommand(vararg args: String): String {
   }
   val ret = process.waitFor()
   if (ret != 0) {
-    throw Exception("command ${args.joinToString(" ")} failed:\n$output")
+    throw Exception("command ${args.joinToString(" ")} failed (ret=$ret):\n$output")
   }
   return output.toString().trim()
 }