chore(deps): bump org.jetbrains.kotlin:kotlin-maven-allopen in /api (#64)

Bumps org.jetbrains.kotlin:kotlin-maven-allopen from 1.9.20 to 1.9.21.

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-maven-allopen
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

api/pom.xml

@@ -15,7 +15,7 @@
 	<description>Demo project for Spring Boot</description>
 	<properties>
 		<java.version>21</java.version>
-		<kotlin.version>1.9.20</kotlin.version>
+		<kotlin.version>1.9.21</kotlin.version>
 		<kotest.version>5.8.0</kotest.version>
 		<mockk.version>1.13.8</mockk.version>
 		<springmockk.version>4.0.2</springmockk.version>