(Java 16+) Support using @Comment and @SerializedName on record components

[Juuxel]

Currently, fetching them (for my WIP record adapter) needs me to reflect the backing field of the record component, as the annotation goes onto the field. Having ElementType.RECORD_COMPONENT as a possible target would make the code cleaner (without the additional getField calls).

Of course, it's only available on Java 16 and newer so this is for the far future 😄