Update registry1.dso.mil/ironbank/opensource/debian/debian Docker tag to v11.8

This MR contains the following updates:

Package	Type	Update	Change
registry1.dso.mil/ironbank/opensource/debian/debian	ironbank-base	minor	11.7 -> 11.8
registry1.dso.mil/ironbank/opensource/debian/debian	final	minor	11.7 -> 11.8

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