aud OIDC/JWT claim can be corrupted with binary data

[bradjones1]

Thanks so much for this awesome library.

In using this locally, I was getting an error when parsing the JWT token's claims, there is binary data output at the start of the query string when using the callback URL/default audience of http://192.168.50.10:8082/kinksters_matching/introduction_received_followup?external_bearer_token.

If I set the audience to something like 1234 it works fine, as do other query callback URLs such as http://192.168.50.10:8082/kinksters_matching/introduction_retry_after_expiry?external_bearer_token. I thought perhaps there was a length limit, however this working URL/audience is longer than the one that is broken. It's also suspicious that the base64-encoded JWT payload consistently goes binary right at the ? in the query string.

I've poked around the sources a bit and haven't found anything relating to the construction of the audience that strikes out at me. However, I'm not really a Golang developer so my debugging is limited here.

Anyone seen something similar to this? Curious how it's very dependent on the URL provided.