PHP needs to be added a language supported for generation.
Here is a non-exhaustive list of things to do:

• Add the language in the options
• Add an additional refiner
• Add refiner to the triage method
• Add unit test for the new refiner methods
• Add the writers
• Add unit tests for the writers
• Add the main language writer to the triage method
• Add the abstractions library
• Add the sample generation for PHP
• Generate Graph client constructor
• Implement method body for execution methods (getAsync() etc) in request builders
• Support OData query parameter methods? (select, expand?)

AB#11113