Update calico/apiserver Docker tag to v3.31.0

This MR contains the following updates:

Package	Type	Update	Change
calico/apiserver		minor	v3.30.4 -> v3.31.0
calico/apiserver	ironbank-docker	minor	v3.30.4 -> v3.31.0
calico/apiserver	stage	minor	v3.30.4 -> v3.31.0

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