Update giggsey/libphonenumber-for-php version.

Problem/Motivation

Cannot currently upgrade to giggsey/libphonenumber-for-php v9.

Steps to reproduce

View the "composer.json" file of this project, which only requires v8.

Proposed resolution

According to the project page, projects should be able to safely use 8 or 9, and the version bump was to keep parity with the Google version.

Could we possibly look to do "giggsey/libphonenumber-for-php": "^8.0 | ^9.0" in composer.json?

Remaining tasks

Make the update and test it.

User interface changes

N/A

API changes

N/A

Data model changes

N/A