Always regenerate a new token on valid client credentials

[tarzan]

So we got this scenario where a client calls our API every 24hrs and calls the token endpoint first every time. Now this token endpoint will just return the currently valid token. But seeing as this token is valid for exactly 24hrs he now sometimes ends up with an invalid token for his request.
I changed the behavior to have the endpoint only return a currently valid access token when it does not expire within the next 5 minutes. always generate a new token on valid client credentials.