cross-fetch in the JavaScript driver doesn't seem to work everywhere

[penberg]

We've had multiple people point out that they had to switch to native fetch() because of some cross-fetch issue.

[penberg]

Looks like this cross-fetch just ignores native fetch: lquixada/cross-fetch#69

[CodingDoug]

I think we can keep using cross-fetch, but don't import it as fetch (which masks the native fetch). Then, check to see if there is a native fetch to use before falling back to cross-fetch.

Alternatively, this might work in the future: lquixada/cross-fetch#138 (comment)