fix: incorrect SICD/SIDD metadata added by tile factory

[edparris]

This change corrects a problem that caused the GDALTileFactory to write incorrect XML metadata with SICD tiles. Metadata of that kind is provided to the underlying gdal.translate() function through a dictionary of keyword arguments. Some of those arguments remain the same for an entire image while others vary from tile to tile. When multiple tiles were created from the same image some arguments were carried forward to other chips due to a programming error (a shallow vs. deep copy of an argument that was itself a list of values). As a consequence all tiles after the first one may have incorrect metatada encoded that was leftover from previous tiles.

Notes

Changes have been verified in an integration test environment and are being released ASAP given the severity of the issue. Follow-on PRs will address the gaps in automated testing.

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