chore(deps): bump kotlin from 2.4.20 to 2.4.21 in /samples/simple-streamable-server - #1114

Submitted dependency-graph-reports/dynamicdependency-graphauto-submission-submit-gradle.json: The snapshot was accepted, but it is not for the default branch. It will not update dependency results for the repository.

Using Java 21 (temurin) with Gradle (using wrapper)