fix for docs issue 11432

[longwuyuan]

What this PR does / why we need it:

• Docs for the mirror annotation had a bug doc error about traffic mirror #11432
• This PR removed the slash / char from the example value, in the annotation documentation for the annotation mirror
• Details are in the issue

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• CVE Report (Scanner found CVE and adding report)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation only

Which issue/s this PR fixes

fixes #11432

How Has This Been Tested?

• Tested locally on kind cluster

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have added unit and/or e2e tests to cover my changes.
• All new and existing tests passed.

cc @rikatz @strongjz @tao12345666333 @Gacko Please review/approve

/triage accepted
/kind bug
/kind documentation
/area docs

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[tao12345666333]

/remove-kind bug

[tao12345666333]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: longwuyuan, tao12345666333

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Needs approval from an approver in each of these files:

• docs/OWNERS [longwuyuan,tao12345666333]

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[Gacko]

/cherry-pick release-1.10

[k8s-infra-cherrypick-robot]

@Gacko: new pull request created: #11446

In response to this:

/cherry-pick release-1.10

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