[FEATURE REQUEST] Add CITATION.bib

[leebrian]

Is this feature for general SeqSender usage or for submitting to a specific database, if so what database?
General

Is your feature request related to a problem? If so please describe.
N/A

Describe the solution you'd like
To help people reference seqsender, please add a CITATION.bib file to the root.

Additional context
This change is consistent with the Influenza Division documentation style guidance (intranet link only).