AdjustDetectorMapTask can raise RuntimeError

The docs to AdjustDetectorMapTask state that the task raises {{ pfs.drp.stella.fitDistortedDetectorMap.FittingError}} and that's what reduceExposure catches. However, in reality the task raises {{RuntimeError(f"Insufficient good lines:

{numGoodLines}

vs

{needNumLines}

")}} which is not caught.

I'd fix the try block, except that this behaviour is explicitly documented, so I'll leave it up to Paul to decide on the proper fix.