Invalid Builtin Defined Name in Xls Reader

Fix #3935. Xls Reader cannot parse user's spreadsheet, failing on a token of 3d. I believe that, according to https://msopenspecs.azureedge.net/files/MS-XLS/%5bMS-XLS%5d.pdf, this represents a PtgAreaErr3d, i.e. an invalid reference. User cannot provide spreadsheet, but was quite forthcoming in providing additional debugging information. I am usually reluctant to make changes without a test case, however, in this case, the action being taken (treat "builtin" defined name as "not builtin" when it cannot be parsed) makes sense, and it satisfies the user's processing.

Author: oleibman

src/PhpSpreadsheet/Reader/Xls.php

@@ -2740,6 +2740,7 @@ private function readDefinedName(): void
                 $formula = $this->getFormulaFromStructure($formulaStructure);
             } catch (PhpSpreadsheetException) {
                 $formula = '';
+                $isBuiltInName = 0;
             }
 
             $this->definedname[] = [