Bug 1867822: Tidy up the artefact attachments_from_id_list() function

- alter files to use attachments_from_id_list()
- alter attachments_from_id_list func params

Change-Id: I32b26586deb2f2a1b6a624f2c7afc4520a1a57ff
Signed-off-by: Lisa Seeto <lisaseeto@catalyst.net.nz>