fix(filemanager): Binaries can be downloaded from a custom CDN

[jan-molak]

closes #96

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[jan-molak]

Just signed the CLA

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CLAs look good, thanks!

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CLAs look good, thanks!

[cnishina]

update the parameters for the JSDoc

[cnishina]

update JSDoc @param for alternativeCDN

[jan-molak]

Thanks for reviewing @cnishina, please see the updated PR addressing the points you've raised.

[cnishina]

LGTM.