Update registry1.dso.mil/ironbank/opensource/python/python39 Docker tag to v3.9.16

This MR contains the following updates:

Package	Type	Update	Change
registry1.dso.mil/ironbank/opensource/python/python39	ironbank-base	patch	v3.9.15 -> v3.9.16
registry1.dso.mil/ironbank/opensource/python/python39	final	patch	v3.9.15 -> v3.9.16
registry1.dso.mil/ironbank/opensource/python/python39	stage	patch	v3.9.15 -> v3.9.16

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