composer(deps): bump composer/class-map-generator from 1.7.2 to 1.7.3

Bumps [composer/class-map-generator](https://github.com/composer/class-map-generator) from 1.7.2 to 1.7.3.
- [Release notes](https://github.com/composer/class-map-generator/releases)
- [Commits](composer/class-map-generator@1.7.2...1.7.3)

---
updated-dependencies:
- dependency-name: composer/class-map-generator
  dependency-version: 1.7.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]