Per https://tools.ietf.org/html/rfc7519#section-4.1.3, the audience
claim can consist of either a single string or an array of strings.
The latter currently causes an error due to the type of aud in
PartialClaims.
Message-Id: <87r1toex8n.fsf@riseup.net>
Change-Id: I6e00791d0ba56cb1e3c029e1b8617c33000d2ab1
Reviewed-on: https://cl.tvl.fyi/c/depot/+/946
Tested-by: BuildkiteCI
Reviewed-by: lukegb <lukegb@tvl.fyi>
