Fix CONTRIBUTING.md instructions

Signed-off-by: William Desportes <[email protected]>

Author: williamdes

CONTRIBUTING.md

@@ -24,12 +24,12 @@ them and to run automated tests on the code.
 
 ## Coding standards
 
-We do follow PSR-1 and PSR-2 coding standards. 
+We do follow PSR-1 and PSR-2 coding standards.
 
-You can use php-cs-fixer to fix the code to match our expectations:
+You can use phpcbf to fix the code to match our expectations:
 
 ```
-php-cs-fixer fix .
+./vendor/bin/phpcbf
 ```
 
 ## Testsuite
@@ -38,7 +38,7 @@ Our code comes with quite comprehensive testsuite, it is automatically executed
 on every commit and pull request, you can also run it locally:
 
 ```
-./vendor/bin/phpunit -c phpunit.xml
+./vendor/bin/phpunit
 ```
 
 The testsuite relies on fixtures of parser states, in case you need to