Remove bintray repositories from kotlin-native build

kotlin-native/build-tools/build.gradle.kts

@@ -43,7 +43,6 @@ repositories {
     maven(buildKotlinCompilerRepo)
     maven("https://cache-redirector.jetbrains.com/maven-central")
     mavenCentral()
-    maven("https://kotlin.bintray.com/kotlinx")
     maven("https://cache-redirector.jetbrains.com/jcenter")
     jcenter()
 }

kotlin-native/build.gradle

@@ -34,12 +34,10 @@ buildscript {
 
     repositories {
         if (UtilsKt.getCacheRedirectorEnabled(project)) {
-            maven { url "https://cache-redirector.jetbrains.com/dl.kotlin.bintray.com/kotlinx" }
             maven { url "https://cache-redirector.jetbrains.com/maven-central" }
             maven { url "https://cache-redirector.jetbrains.com/jcenter" }
         }
         else {
-            maven { url "https://kotlin.bintray.com/kotlinx" }
             mavenCentral()
             jcenter()
         }

kotlin-native/platformLibs/build.gradle

@@ -15,7 +15,6 @@ buildscript {
         maven {
             url project.bootstrapKotlinRepo
         }
-        maven { url UtilsKt.redirectIfEnabled(project, "https://kotlin.bintray.com/kotlinx") }
     }
 }
 // These properties are used by the 'konan' plugin, thus we set them before applying it.