Bump multiplatform from 2.0.21 to 2.1.20

Bumps [multiplatform](https://github.com/JetBrains/kotlin) from 2.0.21 to 2.1.20.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.21...v2.1.20)

---
updated-dependencies:
- dependency-name: multiplatform
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

build.gradle.kts

@@ -2,7 +2,7 @@ import java.util.*
 import io.gitlab.arturbosch.detekt.*
 
 plugins {
-    kotlin("multiplatform") version "2.0.21"
+    kotlin("multiplatform") version "2.1.20"
     kotlin("plugin.compose") version "2.0.21"
     id("org.jetbrains.compose") version "1.7.0"
     id("maven-publish")