Bump ts-loader from 8.0.17 to 8.0.18 in /glean (#117)

Bumps [ts-loader](https://github.com/TypeStrong/ts-loader) from 8.0.17 to 8.0.18.
- [Release notes](https://github.com/TypeStrong/ts-loader/releases)
- [Changelog](https://github.com/TypeStrong/ts-loader/blob/master/CHANGELOG.md)
- [Commits](TypeStrong/ts-loader@v8.0.17...v8.0.18)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>