Update dependency org.jetbrains.kotlin:kotlin-stdlib-jdk8 to v2.1.21

Author: renovate[bot]

buildSrc/src/main/kotlin/dependencies/Versions.kt

@@ -5,7 +5,7 @@ object Versions {
     const val activity_ktx = "1.10.1"
     const val core_ktx = "1.15.0"
     const val android_annotation = "1.9.1"
-    const val kotlin = "2.1.10"
+    const val kotlin = "2.1.21"
 
     // UI
     const val appcompat = "1.7.0"