Update calico/node Docker tag to v3.21.4

This MR contains the following updates:

Package	Type	Update	Change
calico/node	ironbank-docker	patch	v3.21.3 -> v3.21.4
calico/node		patch	v3.21.3 -> v3.21.4
calico/node	stage	patch	v3.21.3 -> v3.21.4

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