ESM configuration module does not work under tsx

[rla]

ESM configuration module does not work under tsx. tsx is runner for TypeScript code.

This happens because migrate-mongo uses exception to try to load ESM-based configuration module:

migrate-mongo/lib/env/config.js

Line 68 in 3753b2b

if (e.code === 'ERR_REQUIRE_ESM') {

but tsx swallows these exceptions as described in its README:
https://github.com/privatenumber/tsx/tree/9c000f04f3381ccd07627e11eea759753c10b839?tab=readme-ov-file#about

I think it's tsx issue but leaving this here since I was not able to file the issue on the tsx tracker. Workaround is to not rely on a configuration file but use config.set: https://github.com/seppevs/migrate-mongo/tree/3753b2bc52436d06482efc8442d10e93960b83f8?tab=readme-ov-file#configsetyourconfigobject

To enable the workaround you might also have to extract and update @types/migrate-mongo because the types are out-of-sync with this package (missing moduleSystem property).