Create pfsDesigns with a larger `dot_margin` factor for the next run in Feb. 2023.

In the Nov run, we made pfsDesigns without any additional margin factor to avoid black dots, so some objects close to the dot were partially vignetted, which made the reduction a little bit hard. In longer run, we will deal with the effects in pipeline and also add penalty as a function of distance from dot when assigning fibers. In shorter run, for the next run in Feb., create pfsDesign with a larger margin with `–dot_margin>1`. The factor may depend on the location on the focal plane, but for now use the fixed factor for all fibers, which should be discussed somewhere taking into consideration the results in Nov. and theoretical prediction using such as spot diagrams.