Merge #719

719: CAD-704 nightly CI job chain-sync not active anymore r=CodiePP a=CodiePP


Issue
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- this PR disables the nightly "chain-sync" job as it is not run on dedicated hardware and will be moved to cardano-benchmarking repo anyway.

- This PR **does not result** in breaking changes to upstream dependencies.

Checklist
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- [x] This PR contains all the work required to resolve the linked issue.

- [ ] The work contained has sufficient documentation to describe what it does and how to do it.

- [ ] The work has sufficient tests and/or testing.

- [x] I have committed clear and descriptive commits. Be considerate as somebody else will have to read these.

- [x] I have added the appropriate labels to this PR.


Co-authored-by: Alexander Diemand <[email protected]>