Remove PHP 8.1 specific syntax from test suite

Author: Slamdunk

tests/_files/source_with_heavy_indentation.php

@@ -55,10 +55,6 @@ public function isOne(): bool
                         =>
                             true
                         ,
-                        $this
-                            ?->
-                            state
-                        ,
                         self
                             ::
                             $state

tests/tests/RawCodeCoverageDataTest.php

@@ -347,8 +347,7 @@ public function testHeavyIndentationIsHandledCorrectly(): void
                 52,
                 54,
                 60,
-                64,
-                75,
+                71,
             ],
             array_keys(RawCodeCoverageData::fromUncoveredFile($file, new ParsingUncoveredFileAnalyser)->lineCoverage()[$file])
         );