Bump ember-resolver from 5.1.3 to 5.2.1

Bumps [ember-resolver](https://github.com/ember-cli/ember-resolver) from 5.1.3 to 5.2.1.
- [Release notes](https://github.com/ember-cli/ember-resolver/releases)
- [Changelog](https://github.com/ember-cli/ember-resolver/blob/master/CHANGELOG.md)
- [Commits](ember-cli/ember-resolver@v5.1.3...v5.2.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>