I've decided to find various points with inputs close to one, using the Desmos Graphing Calculator. You can find what I did here, though you could easily replicate this yourself. Setting the value of a to oscillate between values closer and closer to one, it became clear that the limit goes towards ln(2). I'm not sure of how to go about this problem otherwise, as this is a special integral, but I think that this solution is a good start towards understanding.
Note: If my logic appears to be faulty, or you would like more help, reply to my comment and I will rectify whatever the issue may be.
I've decided to find various points with inputs close to one, using the Desmos Graphing Calculator. You can find what I did here, though you could easily replicate this yourself. Setting the value of a to oscillate between values closer and closer to one, it became clear that the limit goes towards ln(2). I'm not sure of how to go about this problem otherwise, as this is a special integral, but I think that this solution is a good start towards understanding.
Note: If my logic appears to be faulty, or you would like more help, reply to my comment and I will rectify whatever the issue may be.