Hasura 1.3.3: Could not verify JWT: JWSError NoUsableKeys

[tjpeden]

After upgrading to Hasura 1.3.3 (from 1.3.2) I get the above error when making JWT authenticated requests. The JWKS file exists (or Hasura wouldn't start) and contains the single key that is being used for signing. I've created a Git Bundle to share a minimal reproduction of the problem but I can't upload it here, however, I did post it on Discord (@TangoJuliett on Discord).