Downgrade to org.jetbrains.kotlinx:kotlinx-serialization-json 1.4.0

Fixes data class casting issue seen when multiple sources have the same shadowed classes.

gradle/kotlinx.versions.toml

@@ -11,7 +11,8 @@ gradle = { module = "org.jetbrains.kotlin:kotlin-gradle-plugin", version.ref = "
 coroutines-core = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core", version.ref = "coroutines_version" }
 coroutines-android = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-android", version.ref = "coroutines_version" }
 
-serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version.ref = "serialization_version" }
+# TODO: 1.4.1 introduces an issue with cached serializers; see https://github.com/Kotlin/kotlinx.serialization/issues/2065
+serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version = "1.4.0" }
 serialization-json-okio = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json-okio", version.ref = "serialization_version" }
 serialization-protobuf = { module = "org.jetbrains.kotlinx:kotlinx-serialization-protobuf", version.ref = "serialization_version" }
 serialization-gradle = { module = "org.jetbrains.kotlin:kotlin-serialization", version.ref = "kotlin_version" }