chore: enable testifylint

[mmorel-35]

Description

Enables testifylint linter and uses testify instead of t.Fatal(f)

[k8s-ci-robot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: mmorel-35
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[k8s-ci-robot]

@mmorel-35: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-bbolt-test-2-cpu-arm64	d0bb7f0	link	true	/test pull-bbolt-test-2-cpu-arm64
pull-bbolt-test-1-cpu-arm64	d0bb7f0	link	true	/test pull-bbolt-test-1-cpu-arm64
pull-bbolt-test-4-cpu-arm64	d0bb7f0	link	true	/test pull-bbolt-test-4-cpu-arm64

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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