Remove `invert` option from kepler_io.read_kepler_light_curve().
Remove `invert` option from kepler_io.read_kepler_light_curve().

Inversion should be done *after* fitting a normalization curve to the stellar variability and dividing it away. Doing it before normalizing may result in unintentionally reversing the inversion. Therefore we remove the option to do it at this point.

PiperOrigin-RevId: 207309650

alexgorban/models,alexgorban/models,derekjchow/models,alexgorban/models,cshallue/models,derekjchow/models,cshallue/models,tombstone/models,cshallue/models,derekjchow/models,tombstone/models,tombstone/models,derekjchow/models,cshallue/models,tombstone/models,tombstone/models,alexgorban/models,tombstone/models,alexgorban/models,cshallue/models,derekjchow/models