vCard v3.0 serialization: SOUND gets explicit VALUE=BINARY (unlike PHOTO and LOGO)

[respiranto]

Version: 4.5.5

This is not a "real" bug, but merely an inconsistency.

SOUND gets an explicit VALUE=BINARY parameter upon serializing, when transformed from a v4.0 data: URI.
This is not the case for PHOTO and LOGO (cannot test KEY due to #678).

When parsing v3.0 with explicit VALUE=BINARY, this is preserved for all of PHOTO, LOGO, SOUND, and KEY.
When parsing v3.0 without explicit VALUE=BINARY, it is not added for PHOTO and LOGO (cannot test SOUND and KEY because of #676).

I suspect this is bug would also happen when parsing version 3.0 without explicit VALUE=BINARY.
I fear this bug may also be present with KEY (which I could not test).