Bleed trail artifacts identified as large galaxies in 90prime/mosaic

[djschlegel]

This is a companion ticket to #637 (bleed trails identified as bright stars). Spurious large galaxies can be found due to incomplete masking of bleed trails 90prime and/or mosaic images. This doesn't appear to be a problem for decam images. Below are the 36 spurious SHAPE_R>10 arcsec, RMAG<21 mag galaxies in dr9k.

https://www.legacysurvey.org/viewer?ra=200.54344&dec=5.0482871&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=200.59636&dec=8.0630958&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=200.59995&dec=8.0624761&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=200.60366&dec=8.0617673&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=201.22158&dec=8.4538605&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=202.28492&dec=5.0835127&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=203.24693&dec=4.9728388&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=203.17709&dec=5.9191152&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=204.22792&dec=7.2395856&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=206.01863&dec=5.0249659&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=206.67902&dec=5.0304453&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=207.09190&dec=5.8926275&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=208.04181&dec=8.1222027&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=208.75586&dec=9.8175002&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=208.91693&dec=8.8284338&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=209.69460&dec=7.2587457&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=211.42452&dec=-1.0928420&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=213.09116&dec=-0.49260239&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=213.09625&dec=0.97843294&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=213.13398&dec=0.97780762&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=213.60881&dec=-1.3487851&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=213.92700&dec=-1.2773412&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=214.40222&dec=0.98047968&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=214.60026&dec=-0.10505459&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=215.44883&dec=-1.4995325&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=215.75408&dec=1.7070899&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=216.07589&dec=0.17139107&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=217.46874&dec=0.43517907&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=219.14277&dec=1.2707074&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=220.90110&dec=-0.84879563&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=220.86972&dec=-0.88893135&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=240.90697&dec=23.666968&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=269.16511&dec=16.468153&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=269.83275&dec=16.567869&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=269.88707&dec=15.324874&zoom=14&layer=dr8
https://www.legacysurvey.org/viewer?ra=269.93401&dec=19.366524&zoom=14&layer=dr8