Bump kotlinx-coroutines-core in /ripple-examples/ripple-kotlin (#83)

Bumps [kotlinx-coroutines-core](https://github.com/Kotlin/kotlinx.coroutines) from 1.4.1-native-mt to 1.4.2.
- [Release notes](https://github.com/Kotlin/kotlinx.coroutines/releases)
- [Changelog](https://github.com/Kotlin/kotlinx.coroutines/blob/master/CHANGES.md)
- [Commits](https://github.com/Kotlin/kotlinx.coroutines/commits/1.4.2)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

ripple-examples/ripple-kotlin/build.gradle

@@ -15,7 +15,7 @@ dependencies {
     testCompile 'junit:junit:4.13.1'
     compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
     compile "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
-    compile "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.1-native-mt"
+    compile "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.2"
     compile "com.fasterxml.jackson.module:jackson-module-kotlin:2.11.3"
 }