chore(deps): update istio/install-cni docker tag to v1.17.8

This MR contains the following updates:

Package	Type	Update	Change
istio/install-cni	ironbank-docker	patch	1.17.7 -> 1.17.8
istio/install-cni		patch	1.17.7 -> 1.17.8
istio/install-cni	stage	patch	1.17.7 -> 1.17.8

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