Ensure CCD tearing mitigation works for all detectors

(Carrying over from INSTRM-7):

According to a recent report from Jim Gunn https://sumire.pbworks.com/w/file/fetch/145332735/Detectors210616.pdf : a provisional solution to the tearing has been found, that also mitigates the effect on biases. But quoting the summary in that report:

[...]A recent short report from the
Rubin/LSST group, however, showed that the effect varies enough from sensor
to sensor in their set that we have to figure out a way to find the effect in R1, 2, and
3 to be sure it works for all our sensors. This is not trivial in a fiber spectrograph, but
I believe that this can be done by taking a single flat exposure during which we move the slit enough to create a special dithered flat, but this must be tested.

This ticket is to track those tests.