Update of php.md - Opening and Closing PHP Tags Section

[edocev]

The Opening and Closing PHP Tags Section - Specifically the case of single lines PHP inside HTML blocks was unclear and not full. Please see the above-proposed suggestion for edit and further improve that part of the documentation

[dingo-d]

Hi @edocev, can you just rebase your PR so that the latest changes are taken into the account?

[ntwb]

Thanks, but let's not add verbiage defining what "must" be used here.

I think before any further changes are added to the handbook for this a consensus on https://github.com/WordPress/WordPress-Coding-Standards/issues/1085 should be reached.

My suggestion is we close this issue and revisit once the above is resolved