chore(deps): update plugin org.jetbrains.kotlin.multiplatform to v2.1.20 (#316)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| org.jetbrains.kotlin.multiplatform | `2.1.10` -> `2.1.20` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/org.jetbrains.kotlin.multiplatform:org.jetbrains.kotlin.multiplatform.gradle.plugin/2.1.20?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/org.jetbrains.kotlin.multiplatform:org.jetbrains.kotlin.multiplatform.gradle.plugin/2.1.20?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/org.jetbrains.kotlin.multiplatform:org.jetbrains.kotlin.multiplatform.gradle.plugin/2.1.10/2.1.20?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.jetbrains.kotlin.multiplatform:org.jetbrains.kotlin.multiplatform.gradle.plugin/2.1.10/2.1.20?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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build.gradle.kts

@@ -3,7 +3,7 @@ import org.jetbrains.kotlin.gradle.targets.js.nodejs.NodeJsRootPlugin.Companion.
 import org.jetbrains.kotlin.gradle.targets.js.yarn.yarn
 
 plugins {
-    kotlin("multiplatform") version "2.1.10"
+    kotlin("multiplatform") version "2.1.20"
     kotlin("plugin.serialization") version "2.1.10"
     id("io.kotest.multiplatform") version "6.0.0.M2"
     distribution