Trim trailing spaces in generated docs of builtins

generators/builtins/common.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
@@ -74,7 +74,7 @@ fun PrintWriter.printDoc(documentation: String, indent: String) {
         this.println("$indent/** $documentation */")
     } else {
         this.println("$indent/**")
-        docLines.forEach { this.println("$indent * $it") }
+        docLines.forEach { this.println("$indent * $it".trimEnd()) }
         this.println("$indent */")
     }
 }