Update the mosaic pipeline to use wcs info from association files

[stscijgbot-rstdms]

Issue RCAL-961 was created on JIRA by David Davis:

The skycell based associations now have the wcs information for the skycell that the data need to be resampled to in the header

    "skycell_wcs_info": "{"pixel_scale": 0.10000000149011612, "ra_cent": 274.2857142857143, "dec_cent": 63.0, "shiftx": 64151.5, "shifty": -110484.5, "nx": 3564, "ny": 3564, "orient": 356.19525146484375, "orientat_projection_center": 0.0}",

The mosaic pipeline should use this in generate_tan_wcs for the coordinate grid to resample to and only use the wcs info from the patch table as a backup.