Remove source map support runtime for webpack

- Browsers support source maps OOB
- source-map-support is necessary to install to make a sense, but now we only include it in bundle w/o installing
- Additional webpack's options like output.library doesn't works with multiple entries if last item is not bundled library

#KT-33288 fixed

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/webpack/KotlinWebpack.kt

@@ -117,8 +117,7 @@ open class KotlinWebpack : DefaultTask(), RequiresNpmDependencies {
             configDirectory = configDirectory,
             bundleAnalyzerReportDir = if (report) reportDir else null,
             devServer = devServer,
-            sourceMaps = sourceMaps,
+            sourceMaps = sourceMaps
-            sourceMapsRuntime = sourceMaps
         )
     )
 

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/webpack/KotlinWebpackConfig.kt

@@ -28,7 +28,6 @@ data class KotlinWebpackConfig(
     var devServer: DevServer? = null,
     val showProgress: Boolean = false,
     val sourceMaps: Boolean = false,
-    val sourceMapsRuntime: Boolean = false,
     val export: Boolean = true,
     val progressReporter: Boolean = false,
     val progressReporterPathFilter: String? = null
@@ -43,7 +42,6 @@ data class KotlinWebpackConfig(
 
         if (sourceMaps) {
             it.add(versions.sourceMapLoader)
-            it.add(versions.sourceMapSupport)
         }
 
         if (devServer != null) {
@@ -106,7 +104,6 @@ data class KotlinWebpackConfig(
 
             appendEntry()
             appendSourceMaps()
-            appendSourceMapsRuntime()
             appendDevServer()
             appendReport()
             appendFromConfigDir()
@@ -180,20 +177,6 @@ data class KotlinWebpackConfig(
         appendln()
     }
 
-    private fun Appendable.appendSourceMapsRuntime() {
-        if (!sourceMapsRuntime) return
-
-        //language=JavaScript 1.8
-        appendln(
-            """
-                // source maps runtime
-                if (!config.entry) config.entry = [];
-                config.entry.push('source-map-support/browser-source-map-support.js');
-                
-            """.trimIndent()
-        )
-    }
-
     private fun Appendable.appendSourceMaps() {
         if (!sourceMaps) return