chore(utils): remove unused ICMP formatters

[natalie-o-perret]

Description

govulncheck ./... reports GO-2026-5970 through the unused utils/icmp package. The package has no callers, exposes no usable API outside its package, and is not linked into the CLI binary.

Remove the dead ICMP formatting package and regenerate vendored dependencies. This also reclassifies golang.org/x/text as an indirect dependency and prunes the casing implementation that was used only by the removed package.

Checklist

(For exoscale contributors)

• Changelog updated (under Unreleased block, and add the Pull Request #number for each bit you add to the CHANGELOG.md)
• Testing

Testing

The following commands passed locally:

go fmt ./...
make lint
go vet ./...
make build
make test-verbose
go test ./...
(cd tests/e2e && go test -v)
golangci-lint run --timeout 4m
govulncheck ./...

The API-free E2E suite passed. govulncheck ./... reported no reachable vulnerabilities. Repeating go mod tidy && go mod vendor produced no further changes.

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Note

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