Use @osmcha/osm-adiff-parser instead of osm-adiff-parser-saxjs

[jake-low]

We recently published a new NPM package, @osmcha/osm-adiff-parser, (source code here) which is intended to replace osm-adiff-parser and osm-adiff-parser-saxjs, neither of which are maintained anymore. The first version of @osmcha/osm-adiff-parser is v2.0.0. It is based on saxjs, so it works both in the browser and in Node, and it supports both CommonJS and ESM. It is functionally compatible with the 1.x versions of both of the other packages, though it has superficial API differences (namely, it returns a Promise rather than taking a callback function).

This PR replaces the osm-adiff-parser-saxjs in changeset-map with @osmcha/osm-adiff-parser. This has no change in observable behavior, and I've tested it to make sure that it works as expected.

See also OSMCha/osm-adiff-service#20

[tordans]

@jake-low just in case you are not aware, please have a look at https://github.com/tordans/osmcha2/tree/main/app/_components/_lib/real-changesets-parser should this part of the app come up. More context on this project is at OSMCha/osmcha-frontend#741