Bump the dependencies group with 2 updates (#68)

* Bump the dependencies group with 2 updates

Bumps the dependencies group with 2 updates: [jvm](https://github.com/JetBrains/kotlin) and [plugin.spring](https://github.com/JetBrains/kotlin).


Updates `jvm` from 2.0.20 to 2.0.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.0.21/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.20...v2.0.21)

Updates `plugin.spring` from 2.0.20 to 2.0.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.0.21/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.20...v2.0.21)

---
updated-dependencies:
- dependency-name: jvm
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: dependencies
- dependency-name: plugin.spring
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: dependencies
...

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

* Update README.md

---------

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Roger Viñas Alcon <[email protected]>

README.md

@@ -1,6 +1,6 @@
 ![CI](https://github.com/rogervinas/spring-cloud-stream-kafka-step-by-step/actions/workflows/ci.yml/badge.svg)
 ![Java](https://img.shields.io/badge/Java-21-blue?labelColor=black)
-![Kotlin](https://img.shields.io/badge/Kotlin-2.0.20-blue?labelColor=black)
+![Kotlin](https://img.shields.io/badge/Kotlin-2.x-blue?labelColor=black)
 ![SpringBoot](https://img.shields.io/badge/SpringBoot-3.3.4-blue?labelColor=black)
 ![SpringCloud](https://img.shields.io/badge/SpringCloud-2023.0.3-blue?labelColor=black)
 

build.gradle.kts

@@ -6,8 +6,8 @@ import org.gradle.api.tasks.testing.logging.TestLogEvent.SKIPPED
 plugins {
   id("org.springframework.boot") version "3.3.4"
   id("io.spring.dependency-management") version "1.1.6"
-  kotlin("jvm") version "2.0.20"
-  kotlin("plugin.spring") version "2.0.20"
+  kotlin("jvm") version "2.0.21"
+  kotlin("plugin.spring") version "2.0.21"
   id("org.jlleitschuh.gradle.ktlint") version "12.1.1"
 }