Update Ironbank to v1.16.1

This MR contains the following updates:

Package	Update	Change
ironbank/tetrate/istio/operator	minor	1.15.1 -> 1.16.1
registry1.dso.mil/ironbank/tetrate/istio/operator	minor	1.15.1-tetratefips-v1 -> 1.16.1-tetratefips-v1

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This MR has been generated by Renovate Bot.