Update Ironbank to v1.19.4

This MR contains the following updates:

Package	Update	Change
registry1.dso.mil/ironbank/opensource/istio/install-cni	patch	1.19.3 -> 1.19.4
registry1.dso.mil/ironbank/opensource/istio/pilot	patch	1.19.3 -> 1.19.4
registry1.dso.mil/ironbank/opensource/istio/proxyv2	patch	1.19.3 -> 1.19.4

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Configuration

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This MR has been generated by Renovate Bot.