Update dependency org.jetbrains.kotlin:kotlin-gradle-plugin to v1.5.21

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.jetbrains.kotlin:kotlin-gradle-plugin (source)	1.5.20 -> 1.5.21

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Release Notes

JetBrains/kotlin

### [`v1.5.21`](https://togithub.com/JetBrains/kotlin/blob/master/ChangeLog.md#​1521) ##### Compiler - [`KT-47320`](https://youtrack.jetbrains.com/issue/KT-47320) "StringConcatException: Mismatched number of concat arguments" String concatenation fails when template contains special character - [`KT-47445`](https://youtrack.jetbrains.com/issue/KT-47445) "definitely not null type parameters is only available since language version 1.6" error in cast expression - [`KT-47446`](https://youtrack.jetbrains.com/issue/KT-47446) Improve warning message INTEGER_OPERATOR_RESOLVE_WILL_CHANGE - [`KT-47447`](https://youtrack.jetbrains.com/issue/KT-47447) False positive INTEGER_OPERATOR_RESOLVE_WILL_CHANGE warning: "expression will be resolved to Int in future releases" - [`KT-47449`](https://youtrack.jetbrains.com/issue/KT-47449) JVM / IR: ClassCastException IrStarProjectionImpl cannot be cast to IrTypeProjection - [`KT-47459`](https://youtrack.jetbrains.com/issue/KT-47459) "IndexOutOfBoundsException: Index 0 out of bounds for length 0" caused by MarkertManager dependency - [`KT-47480`](https://youtrack.jetbrains.com/issue/KT-47480) StackOverflowError: Recursion on erasion of raw type with interdependent type parameters ##### Tools. Compiler Plugins - [`KT-47161`](https://youtrack.jetbrains.com/issue/KT-47161) Serializable class can't be inherited from serializable class in other module with: e: org.jetbrains.kotlin.codegen.CompilationException: Back-end (JVM) Internal error: Couldn't transform method node: write$Self - [`KT-47455`](https://youtrack.jetbrains.com/issue/KT-47455) Kotlin lombok plugin NullPointerException - [`KT-47513`](https://youtrack.jetbrains.com/issue/KT-47513) Lombok compiler plugin failed with 'Recursion detected in a lazy value under [LockBasedStorageManager@`1c21db6`](https://togithub.com/LockBasedStorageManager/kotlin/commit/1c21db60) (TopDownAnalyzer for JVM)' ##### Tools. Gradle - [`KT-47444`](https://youtrack.jetbrains.com/issue/KT-47444) Gradle Plugin: Publishing project with "maven-publish" fails when dependency versions are omitted (NPE in MppDependencyRewritingUtilsKt.associateDependenciesWithActualModuleDependencies) ##### Tools. kapt - [`KT-47416`](https://youtrack.jetbrains.com/issue/KT-47416) Kapt Gradle DSL ignores javaCompilerOptions in 1.5.20

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