Generic/DisallowLongArraySyntax: remove unreachable condition

A check was added to the top of the file in 8d2a9dd to return an error
early if the array is missing an opening and/or a closing parenthesis.
This means that `$opener` can never be null as when the code reaches the
point where this variable is set,
`$tokens[$stackPtr]['parenthesis_opener']` cannot be null.

Author: rodrigoprimo

src/Standards/Generic/Sniffs/Arrays/DisallowLongArraySyntaxSniff.php

@@ -59,13 +59,9 @@ public function process(File $phpcsFile, $stackPtr)
 
             $phpcsFile->fixer->beginChangeset();
 
-            if ($opener === null) {
-                $phpcsFile->fixer->replaceToken($stackPtr, '[]');
-            } else {
-                $phpcsFile->fixer->replaceToken($stackPtr, '');
-                $phpcsFile->fixer->replaceToken($opener, '[');
-                $phpcsFile->fixer->replaceToken($closer, ']');
-            }
+            $phpcsFile->fixer->replaceToken($stackPtr, '');
+            $phpcsFile->fixer->replaceToken($opener, '[');
+            $phpcsFile->fixer->replaceToken($closer, ']');
 
             $phpcsFile->fixer->endChangeset();
         }