fix(deps): update kotlin monorepo to v2.3.21 (#1249)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Adoption](https://docs.renovatebot.com/merge-confidence/) |
[Passing](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|---|---|
| [org.jetbrains.kotlin:kotlin-stdlib-jdk8](https://kotlinlang.org/)
([source](https://redirect.github.com/JetBrains/kotlin)) | `2.3.20` →
`2.3.21` |
![age](https://developer.mend.io/api/mc/badges/age/maven/org.jetbrains.kotlin:kotlin-stdlib-jdk8/2.3.21?slim=true)
|
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|
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|
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|
| [org.jetbrains.kotlin:kotlin-reflect](https://kotlinlang.org/)
([source](https://redirect.github.com/JetBrains/kotlin)) | `2.3.20` →
`2.3.21` |
![age](https://developer.mend.io/api/mc/badges/age/maven/org.jetbrains.kotlin:kotlin-reflect/2.3.21?slim=true)
|
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|
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|

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gradle/libs.versions.toml

@@ -4,7 +4,7 @@ springBoot = "4.0.5"
 kotest = "6.1.11"
 spotless = "8.4.0"
 detekt = "2.0.0-alpha.2"
-kotlin = "2.3.20"
+kotlin = "2.3.21"
 
 [libraries]
 springdoc = { module = "org.springdoc:springdoc-openapi-starter-webflux-ui", version.ref = "springdoc" }