Upgrade node-fetch to v3

[giordano]

We're currently using node-fetch v2.6.7, but v3 was released a few months ago. We may want to use the latest version. #92 already tried to upgrade to v3 but tests failed, so we may need manual intervention to deal with the new major version (reasonable since v3 is a breaking change compared to v2). Here are the upgrade instructions.

[ageorgou]

The error appears to be linked to producing (old style) require statements instead of (newer style) import. In v3 of node-fetch, only the latter is supported. Our Typescript code uses import but it seems to be compiled down to require in the actual Javascript. It looks like we need some changes to our config files to force the switch (and possibly our other import statements).

[giordano]

James reported:

Experimental support for the fetch api is now in Node.js version 18