Fixed upgrading example command

[valentinsoe]

What this PR does / why we need it:
Fixing error in docymentation

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #
fixes #4682

Special notes for your reviewer:

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[k8s-ci-robot]

Hi @valentinsoe. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[aledbf]

/ok-to-test

[aledbf]

Please sign the CLA

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@be277f8). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #4683   +/-   ##
=========================================
  Coverage          ?   58.68%           
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  Files             ?       88           
  Lines             ?     6762           
  Branches          ?        0           
=========================================
  Hits              ?     3968           
  Misses            ?     2357           
  Partials          ?      437

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[valentinsoe]

I signed it

[aledbf]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf, valentinsoe

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