[skip ci] Bump the dev-deps group across 1 directory with 2 updates

Bumps the dev-deps group with 2 updates in the /deps/rabbitmq_auth_backend_http/examples/rabbitmq_auth_backend_spring_boot_kotlin directory: [org.jetbrains.kotlin:kotlin-test](https://github.com/JetBrains/kotlin) and org.jetbrains.kotlin:kotlin-maven-allopen.


Updates `org.jetbrains.kotlin:kotlin-test` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin:kotlin-maven-allopen` from 2.1.20 to 2.1.21

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-test
  dependency-version: 2.1.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dev-deps
- dependency-name: org.jetbrains.kotlin:kotlin-maven-allopen
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: dev-deps
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

deps/rabbitmq_auth_backend_http/examples/rabbitmq_auth_backend_spring_boot_kotlin/pom.xml

@@ -23,7 +23,7 @@
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 		<maven.compiler.source>17</maven.compiler.source>
 		<maven.compiler.target>17</maven.compiler.target>
-		<kotlin.version>2.1.20</kotlin.version>
+		<kotlin.version>2.1.21</kotlin.version>
 		<junit-jupiter.version>5.10.0</junit-jupiter.version>
 	</properties>