Switch to native `fetch()`

[thislooksfun]

Node 17.5.0 adds an implementation of fetch(). This is great as it will allow dropping got as a dependency, which will, in turn, allow for snoots to work in the browser (perhaps not out-of-the-gate, but still).

The catch is that the fetch() implementation is experimental and also currently only in the latest odd release. Once it becomes stable in an LTS release we should switch to it.