auth: Hard-code node-fetch version

[nturinski]

Fixes microsoft/vscode-azurefunctions#3878

There's a lot of weirdness going on here, but the gist of it is whenever fetch is called before @azure/client-core, it is overwriting the node-fetch package that is used for most of our requests (because we generate our ServiceClients with core-client).

For whatever reason, >= v3.7.0 are causing zipdeploy to fail in App Service/Functions, but only on Windows machines. I've investigated a lot and can't pinpoint the exact reason, but my guess is that the socket isn't closing at the same time as it was on earlier versions.

I've spent a lot of time trying to figure this one out, but have thrown in the hat in terms of understanding exactly why/how this is happening. 😐

[motm32]

I can confim from my stinkpad that this fixes the issue for me🥳

[alexweininger]

🥴

[bwateratmsft]

How strange...