Handle situation where KSerializer is absent from immediate supertypes

of the class used in @UseSerializers: Use methods to receive
full list of supertypes.

K1 supertypes() call returned all supertypes, while
IrClass.supertypes and FirClassSymbol.resolvedSuperTypes return only immediate ones.

This lead to a difference in behavior between K1 and K2, and regression
after plugin backend was rewritten from descriptors to IR.

#KT-55340 Fixed

plugins/kotlinx-serialization/kotlinx-serialization.common/src/org/jetbrains/kotlinx/serialization/compiler/resolve/NamingConventions.kt

@@ -208,6 +208,8 @@ object SerializersClassIds {
     val sealedSerializerId = ClassId(SerializationPackages.packageFqName, Name.identifier(SpecialBuiltins.sealedSerializer))
     val contextSerializerId = ClassId(SerializationPackages.packageFqName, Name.identifier(SpecialBuiltins.contextSerializer))
     val generatedSerializerId = ClassId(SerializationPackages.internalPackageFqName, SerialEntityNames.GENERATED_SERIALIZER_CLASS)
+
+    val setOfSpecialSerializers = setOf(contextSerializerId, polymorphicSerializerId)
 }
 
 fun findStandardKotlinTypeSerializerName(typeName: String?): String? {