chore(deps): update plugin org.jetbrains.kotlin.multiplatform to v2.3.20 (#470)

This PR contains the following updates:

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| org.jetbrains.kotlin.multiplatform | `2.3.10` → `2.3.20` |
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build.gradle.kts

@@ -3,7 +3,7 @@ import org.jetbrains.kotlin.gradle.targets.js.nodejs.NodeJsEnvSpec
 import org.jetbrains.kotlin.gradle.targets.js.yarn.YarnRootEnvSpec
 
 plugins {
-    kotlin("multiplatform") version "2.3.10"
+    kotlin("multiplatform") version "2.3.20"
     kotlin("plugin.serialization") version "2.3.10"
     id("io.kotest") version "6.0.7"
     id("com.google.devtools.ksp") version "2.3.6"