Bump url_launcher from 6.1.8 to 6.1.9

Bumps [url_launcher](https://github.com/flutter/plugins/tree/main/packages/url_launcher) from 6.1.8 to 6.1.9.
- [Release notes](https://github.com/flutter/plugins/releases)
- [Commits](https://github.com/flutter/plugins/commits/url_launcher-v6.1.9/packages/url_launcher)

---
updated-dependencies:
- dependency-name: url_launcher
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]