Update Kotlin [1.3.50 -> 1.3.61], coroutines [1.3.1 -> 1.3.3].

Most notably coroutines may fix
IllegalStateException: Module with the Main dispatcher is missing.
Kotlin/kotlinx.coroutines#1532

Author: UweTrottmann

build.gradle

@@ -1,7 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 buildscript {
-    ext.kotlin_version = '1.3.50' // https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md
-    ext.coroutines_version = '1.3.1' // https://github.com/Kotlin/kotlinx.coroutines/blob/master/CHANGES.md
+    ext.kotlin_version = '1.3.61' // https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md
+    ext.coroutines_version = '1.3.3' // https://github.com/Kotlin/kotlinx.coroutines/blob/master/CHANGES.md
     ext.versions = [
             'minSdk': 21,
             'compileSdk': 28,