Squiz/OperatorBracket: bug fix - improve recognition of unary minus

The new test was giving _three_ instead of _two_ errors on line 194 for this snippet `$padding * -1 + 3`, with the errors being thrown on the `*`, `-` and the `+` operators.

The `-` operator, however, is a unary operator and should not trigger this error.

Fixed now.

Author: jrfnl

src/Standards/Squiz/Sniffs/Formatting/OperatorBracketSniff.php

@@ -80,7 +80,8 @@ public function process(File $phpcsFile, $stackPtr)
                     $isAssignment = isset(Tokens::$assignmentTokens[$tokens[$previous]['code']]);
                     $isEquality   = isset(Tokens::$equalityTokens[$tokens[$previous]['code']]);
                     $isComparison = isset(Tokens::$comparisonTokens[$tokens[$previous]['code']]);
-                    if ($isAssignment === true || $isEquality === true || $isComparison === true) {
+                    $isUnary      = isset(Tokens::$operators[$tokens[$previous]['code']]);
+                    if ($isAssignment === true || $isEquality === true || $isComparison === true || $isUnary === true) {
                         // This is a negative assignment or comparison.
                         // We need to check that the minus and the number are
                         // adjacent.

src/Standards/Squiz/Tests/Formatting/OperatorBracketUnitTest.php

@@ -71,7 +71,7 @@ public function getErrorList($testFile='OperatorBracketUnitTest.inc')
                 185 => 1,
                 189 => 1,
                 193 => 1,
-                194 => 3,
+                194 => 2,
             ];
             break;
         case 'OperatorBracketUnitTest.js':