Change domain default to `~`

[sodoku]

After this plugin wasn't working for me, I figured out that the default for domains (sentry calls this url prefix) should be ~. See https://github.com/getsentry/sentry-cli/blob/master/docs/releases.rst#upload-source-maps

[AmberWilkie]

Yes please merge this! I was going to implement it in my own (and I will) but this is the only thing breaking for me with my implementation.

[AmberWilkie]

For everyone that comes after, you can add DOMAIN: '~' to your implementation and it will work - you don't need to fork the repo for this. My implementation looks like this:

  const sentryRelease = plugins.sentryRelease({
    API_URL: sentryUrl,
    API_KEY: process.env.SENTRY_API_KEY,
    version: versionString,
    DOMAIN: '~'
  });