Update Ironbank Docker tags to v1.9.4

This MR contains the following updates:

Package	Update	Change
ironbank/hashicorp/vault/vault	patch	1.9.3 -> 1.9.4
registry1.dso.mil/ironbank/hashicorp/vault/vault	patch	1.9.3 -> 1.9.4

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This MR has been generated by Renovate Bot.

For issue https://repo1.dso.mil/platform-one/big-bang/apps/sandbox/vault/-/issues/13