Fix CI fuzz job yml syntax

[Rot127]

Your checklist for this pull request

• I've documented or updated the documentation of every API function and struct this PR changes.
• I've added tests that prove my fix is effective or that my feature works (if possible)

Detailed description

The syntax in the yml file was off and we didn't catch it for the last three weeks.

Test plan

This one should be merged red (in the end it doesn't make a difference).
Then we need Google to merge the PR which updates setuptools in the docker image.

Afterwards we can check it again.

Closing issues

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