[26.0] Fix webdav file download

[davelopez]

Fixes #22681
Forgot to upstream this fix from EU.
This can be dropped when merging forward, since the webdav file source was refactored and migrated to fsspec in #22477

How to test the changes?

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

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