Update ksp monorepo to v2.1.21-2.0.1

Author: renovate[bot]

gradle/libs.versions.toml

@@ -15,7 +15,7 @@ junit = "4.13.2"
 kotlin = "2.1.20"
 kotlinxCollectionsImmutable = "0.3.8"
 kotlinxCoroutines = "1.10.2"
-ksp = "2.1.20-2.0.1"
+ksp = "2.1.21-2.0.1"
 ktlint = "12.2.0"
 lifecycle = "2.9.0"
 # @keep