Ensure bundle file is saved with file extension (fix #2618)

[Ifeanyi Oraelosi (gnerkus)]

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• fetch the user's file type selection
• if no list of file types, default to .json

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Closes #2618

[Martí Climent (marticliment)]

Looks good for me, I will test it out later this month and merge it

[Martí Climent (marticliment)]

Don't worry about merging main into your branch, I will do this when testing the PR

[Ifeanyi Oraelosi (gnerkus)]

Don't worry about merging main into your branch, I will do this when testing the PR

Got it.