Bump ember-power-select from 7.2.0 to 8.12.1

Bumps [ember-power-select](https://github.com/cibernox/ember-power-select) from 7.2.0 to 8.12.1.
- [Release notes](https://github.com/cibernox/ember-power-select/releases)
- [Changelog](https://github.com/cibernox/ember-power-select/blob/master/CHANGELOG.md)
- [Commits](ember-power-addons/ember-power-select@v7.2.0...v8.12.1)

---
updated-dependencies:
- dependency-name: ember-power-select
  dependency-version: 8.12.1
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]