This project is a fork of php.vim--Garvin which in turn is an update of the php.vim script which in turn is an updated version of the php.vim syntax file distributed with Vim. Whew!
The project comes with a Dockerfile which can be used to rebuild the syntax file.
docker build -t StanAngeloff/php.vim .
docker run -i -t StanAngeloff/php.vim /build/update_syntax.php | sed 's/\x0D$//' > syntax/php.vim