📖Fix remediation test doc issue in v1.3 to v1.4 upgrade docs

[willie-yao]

What this PR does / why we need it:
This PR fixes a documentation error in the v1.3 to v1.4 upgrade docs.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #8499

[fabriziopandini]

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: d7c91dd9552d2da593814f4ecc7ec58bb20a0f66

[fabriziopandini]

/cherry-pick release-1.4

[k8s-infra-cherrypick-robot]

@fabriziopandini: once the present PR merges, I will cherry-pick it on top of release-1.4 in a new PR and assign it to you.

In response to this:

/cherry-pick release-1.4

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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• docs/OWNERS [fabriziopandini]

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[k8s-infra-cherrypick-robot]

@fabriziopandini: new pull request created: #8512

In response to this:

/cherry-pick release-1.4

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.