hook_requirements deprecated in favor of separate runtime and update hooks and install-time requirements checks

Note that while the deprecation is only formalized in 11.3, all replacements are available in Drupal 11.2.

See the following change records on how to update each previous phase:

• There is a new InstallRequirementsInterface to provide install time requirements.
• Added hook_runtime_requirements() and hook_runtime_requirements_alter()
• Added hook_update_requirements() and hook_update_requirements_alter()