Remove old folder for conan install (#5376)

[uilianries]

• Run rmdir before creating a new temp folder

Changelog: Fix: Remove old folder for conan install (#5376)
Docs: Omit
fixes #5376

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[lasote]

I think it would be better to remove the folder at the beginning if it exists to avoid creating N dirty folders.

[lasote]

I think the test can be easier now. Just write a file after the first call and check after the second that the file is not there anymore.

[jgsogo]

And please, @uilianries , change the changelog according to the behavior.

[uilianries]

@jgsogo done!