Deprecate join (use joinToString instead)

#KT-6909

libraries/tools/kotlin-gradle-plugin-core/src/main/kotlin/org/jetbrains/kotlin/gradle/tasks/Tasks.kt

@@ -278,7 +278,7 @@ public open class Kotlin2JsCompile() : AbstractKotlinCompile<K2JSCompilerArgumen
             }
         }
 
-        getLogger().debug("${getName()} set libraryFiles to ${args.libraryFiles.join(",")}")
+        getLogger().debug("${getName()} set libraryFiles to ${args.libraryFiles.joinToString(",")}")
         getLogger().debug("${getName()} set outputFile to ${args.outputFile}")
 
     }

libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt

@@ -139,7 +139,7 @@ abstract class BaseGradleIT {
             listOf("/bin/bash", "./gradlew") + tailParameters
     }
 
-    private fun String.normalize() = this.lineSequence().join(SYSTEM_LINE_SEPARATOR)
+    private fun String.normalize() = this.lineSequence().joinToString(SYSTEM_LINE_SEPARATOR)
 
     private fun isWindows(): Boolean {
         return System.getProperty("os.name")!!.contains("Windows")

libraries/tools/kotlin-js-tests-junit/src/main/kotlin/org/jetbrains/kotlin/js/qunit/SeleniumQUnit.kt

@@ -78,7 +78,7 @@ public class SeleniumQUnit(val driver: WebDriver) {
 
             for (message in failMessages)
                 println("FAILED: $message")
-            fail(failMessages.join("\n"))
+            fail(failMessages.joinToString("\n"))
         }
     }
 

libraries/tools/kotlin-stdlib-gen/src/templates/Engine.kt

@@ -384,7 +384,7 @@ class GenericFunction(val signature: String, val keyword: String = "fun") {
 
         val types = effectiveTypeParams()
         if (!types.isEmpty()) {
-            builder.append(types.join(separator = ", ", prefix = "<", postfix = "> ").renderType())
+            builder.append(types.joinToString(separator = ", ", prefix = "<", postfix = "> ").renderType())
         }
 
         val receiverType = (if (toNullableT) receiver.replace("T>", "T?>") else receiver).renderType()