Update registry1.dso.mil/ironbank/opensource/python Docker tag to v3.12.3

This MR contains the following updates:

Package	Type	Update	Change
registry1.dso.mil/ironbank/opensource/python (source)	final	minor	v3.11.9 -> v3.12.3
registry1.dso.mil/ironbank/opensource/python (source)	stage	minor	v3.11.9 -> v3.12.3

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