Fix the "Get Distribution Export" polling logic

[eyalbe4]

Modify the logic of the code that waits for the distribution export to finish.
Instead of waiting of the a completion signal from the API, we're also waiting for the relative path to not be "" or "/"

[github-actions]

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✅ (eyalbe4)[https://github.com/eyalbe4]
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