Drop kotin/kotlinx and kotlin/kotlinx.html bintray usages (KTI-528)

compiler/fir/dump/build.gradle.kts

@@ -8,10 +8,6 @@ plugins {
     id("jps-compatible")
 }
 
-repositories {
-    maven { setUrl("https://dl.bintray.com/kotlin/kotlinx.html/") }
-}
-
 dependencies {
     implementation(project(":core:descriptors"))
     implementation(project(":core:deserialization"))

compiler/fir/resolve/build.gradle.kts

@@ -3,10 +3,6 @@ plugins {
     id("jps-compatible")
 }
 
-repositories {
-    maven(url = "https://dl.bintray.com/kotlin/kotlinx")
-}
-
 dependencies {
     api(project(":core:compiler.common"))
     api(project(":compiler:resolution.common"))