minor #39772 Simplify PHP CS Fixer config (keradus)

This PR was merged into the 4.4 branch.

Discussion
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Simplify PHP CS Fixer config

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       | n/a
| License       | MIT
| Doc PR        |

same rules, just written in easier way

Commits
-------

95e33edc1c Simplify PHP CS Fixer config

.php_cs.dist

@@ -6,18 +6,13 @@ if (!file_exists(__DIR__.'/src')) {
 
 return PhpCsFixer\Config::create()
     ->setRules([
+        '@PHP71Migration' => true,
+        '@PHPUnit75Migration:risky' => true,        
         '@Symfony' => true,
         '@Symfony:risky' => true,
-        '@PHPUnit75Migration:risky' => true,
-        'php_unit_dedicate_assert' => ['target' => '5.6'],
-        'array_syntax' => ['syntax' => 'short'],
-        'fopen_flags' => false,
         'protected_to_private' => false,
         'native_constant_invocation' => true,
-        'combine_nested_dirname' => true,
         'list_syntax' => ['syntax' => 'short'],
-        'visibility_required' => ['property', 'method', 'const'],
-        'ternary_to_null_coalescing' => true,
     ])
     ->setRiskyAllowed(true)
     ->setFinder(