JWT iat claim may cause "token used before issue"

[vlad-nefodov]

When manually setting the issuedAt (iat) claim in Stream Chat JWT tokens, authentication can fail with:

userClient.CreateToken(
                    userId: command.UserId.ToString(),
                    expiration: DateTimeOffset.UtcNow.AddMinutes(streamChatConfiguration.TokenLifetimeMinutes),
                    issuedAt: DateTimeOffset.UtcNow);

I suspect this issue may be related to the lack of clock skew tolerance on the server side or a similar strict validation mechanism.