[8.x] [Discover] Unskip and improve serverless csv functional test (#…

…202396) (#204624)

# Backport

This will backport the following commits from `main` to `8.x`:
- [[Discover] Unskip and improve serverless csv functional test
(#202396)](#202396)

<!--- Backport version: 8.9.8 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

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Unskip and improve serverless csv functional test
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Unskip and improve serverless csv functional test
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Unskip and improve serverless csv functional test
(#202396)","sha":"50713ca6d858593cac3cec59d1a53b46a675f635"}}]}]
BACKPORT-->