chore(deps): update all non-major dependencies to v2.1.21 (#28)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

build.gradle.kts

@@ -1,6 +1,6 @@
 plugins {
-    kotlin("multiplatform") version "2.1.10" apply false
-    kotlin("plugin.compose") version "2.1.10" apply false
+    kotlin("multiplatform") version "2.1.21" apply false
+    kotlin("plugin.compose") version "2.1.21" apply false
     id("com.android.library") version "8.10.0" apply false
     id("org.jetbrains.dokka") version "2.0.0" apply false
     id("org.jetbrains.compose") version "1.8.0" apply false