Upgrade kotlin

Author: hieuwu

gradle/libs.versions.toml

@@ -45,7 +45,7 @@ javalite = "3.25.5"
 jsonassert = "1.5.0"
 kotest = "5.9.0" # Do not use 5.9.1 because it reverts the fix for https://github.com/kotest/kotest/issues/3981
 kotestAssertionsCore = "5.8.1"
-kotlin = "1.8.22"
+kotlin = "2.1.0"
 ktorVersion = "3.1.3"
 legacySupportV4 = "1.0.0"
 lifecycleProcess = "2.3.1"