chore(deps): update kotlin core dependencies to v1.8.21

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
org.jetbrains.kotlin.plugin.serialization (source)	1.8.20 -> 1.8.21
org.jetbrains.kotlin.multiplatform (source)	1.8.20 -> 1.8.21
org.jetbrains.kotlin:kotlin-serialization (source)	1.8.20 -> 1.8.21
org.jetbrains.kotlin:kotlin-gradle-plugin (source)	1.8.20 -> 1.8.21

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Release Notes

JetBrains/kotlin

v1.8.21

Compiler

• KT-57848 Native: compilation of dynamic/static library fails with Xcode 14.3
• KT-57875 Native compilation failure: Suspend functions should be lowered out at this point, but FUN LOCAL_FUNCTION_FOR_LAMBDA
• KT-57946 KAPT: "RuntimeException: No type for expression" with delegate

JavaScript

• KT-57356 KJS: StackOverflowException on @​JsExport with type parameters referring to one another

Tools. Compiler plugins. Serialization

• KT-58067 Serialization: NullPointerException caused by @​Contextual property with type with generic
• KT-57730 Serialization: "IllegalStateException: Serializer for element of type .Foo has not been found" caused by serialization of Java type

Tools. Gradle. JS

• KT-57766 KJS / Gradle "Module not found: Error: Can't resolve 'kotlin-kotlin-stdlib-js-ir'" when using "useEsModules"

Tools. Kapt

• KT-58027 Kotlin 1.8.20 kapt issue "null: KtCallExpression: build()"

Tools. Maven

• KT-58048 Maven: "Too many source module declarations found" after upgrading to 1.8.20
• KT-58101 'Unable to access class' in kotlin-maven-plugin after updating to Kotlin 1.8.20

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[github-actions]

JUnit Tests (Linux, EnricoMi/publish-unit-test-result-action@v1)

245 tests  ±0   221 ✔️ ±0   12m 44s ⏱️ + 2m 40s
  48 suites ±0     24 💤 ±0 
  48 files   ±0       0 ❌ ±0 

Results for commit e654345. ± Comparison against base commit 77ae870.

[github-actions]

JUnit Tests (Windows, EnricoMi/publish-unit-test-result-action@v1)

245 tests  ±0   221 ✔️ ±0   12m 36s ⏱️ + 1m 18s
  48 suites ±0     24 💤 ±0 
  48 files   ±0       0 ❌ ±0 

Results for commit e654345. ± Comparison against base commit 77ae870.

[github-actions]

JUnit Tests (macOS, EnricoMi/publish-unit-test-result-action@v1)

245 tests  ±0   221 ✔️ ±0   18m 34s ⏱️ + 3m 49s
  48 suites ±0     24 💤 ±0 
  48 files   ±0       0 ❌ ±0 

Results for commit e654345. ± Comparison against base commit 77ae870.

[codecov]

Codecov Report

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@@           Coverage Diff           @@
##             main     #529   +/-   ##
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  Coverage        ?   48.32%           
  Complexity      ?      164           
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  Files           ?       53           
  Lines           ?     1877           
  Branches        ?      313           
=======================================
  Hits            ?      907           
  Misses          ?      841           
  Partials        ?      129           

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unittests	48.32% <ø> (?)

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