Revert "Remove phpcs standard"

This reverts commit d6068ed38d.

As I use PSR12 most of the time and Ale will fall back to a different
standard.

home/programs/neovim/plugins/ale.vim

@@ -23,6 +23,8 @@ let g:ale_lint_on_text_changed = 'never'
 let g:ale_sign_error = '>'
 let g:ale_sign_warning = '!'
 
+let g:ale_php_phpcs_standard = 'PSR12'
+
 let g:ale_php_phpstan_executable = 'vendor/bin/phpstan'
 
 call ale#handlers#languagetool#DefineLinter('rst')