Squiz/OperatorSpacing: move parse error test to own test case file

Author: jrfnl

src/Standards/Squiz/Tests/WhiteSpace/OperatorSpacingUnitTest.1.inc

@@ -482,6 +482,3 @@ match ($a) {
     'b', 'c', 'd' => -2,
     default => -3,
 };
-
-/* Intentional parse error. This has to be the last test in the file. */
-$a = 10 +

src/Standards/Squiz/Tests/WhiteSpace/OperatorSpacingUnitTest.1.inc.fixed

@@ -476,6 +476,3 @@ match ($a) {
     'b', 'c', 'd' => -2,
     default => -3,
 };
-
-/* Intentional parse error. This has to be the last test in the file. */
-$a = 10 +

src/Standards/Squiz/Tests/WhiteSpace/OperatorSpacingUnitTest.3.inc

@@ -0,0 +1,6 @@
+<?php
+
+// Intentional parse error (unfinished statement).
+// This has to be the only test in the file.
+
+$a = 10 +