fix: Use correct writer

[mrueg]

What this PR does / why we need it:

Use the correct writer to write the EOF

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)
None

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 #2036

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[CatherineF-dev]

/lgtm
/hold
wait #2036 test it

[dgrisonnet]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: CatherineF-dev, dgrisonnet, mrueg

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[dgrisonnet]

Unholding since it has been proven to work: #2036 (comment)

/unhold

[AleksaC]

Any info as to when will this land into a release?