[go] Bump images, dependencies and versions to go 1.21.6 and distroless iptables to 0.4.4

[cpanato]

What type of PR is this?

/kind feature

What this PR does / why we need it:

• Bump images, dependencies and versions to go 1.21.6 and distroless iptables to 0.4.4

/assign @liggitt @dims @xmudrii @saschagrunert
cc @kubernetes/release-engineering

Which issue(s) this PR fixes:

xref kubernetes/release#3412

Does this PR introduce a user-facing change?

Kubernetes is now built with Go 1.21.6

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[k8s-ci-robot]

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[ameukam]

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: a234c6c3931897ec6b1ada77921f64c428521211

[xmudrii]

/retest

[xmudrii]

/lgtm
/approve

[xmudrii]

/retest

[dims]

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 738b76062a0e02d3b6b9f17b0fd82ae5dcde2972

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, dims, xmudrii

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• test/images/OWNERS [dims]
• test/utils/image/OWNERS [dims]

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