compound assignment

Author: ianfnelson

src/ServiceLayer.Mesh/FileTypes/NbssAppointmentEvents/FileParser.cs

@@ -64,7 +64,7 @@ public ParsedFile Parse(Stream stream)
                     break;
 
                 default:
-                    recordIdentifier = recordIdentifier ?? "No Record Identifier found";
+                    recordIdentifier ??= "No Record Identifier found";
                     throw new FileParsingException(
                         ErrorCodes.UnknownRecordTypeIdentifier,
                         $"Unknown Record Identifier {recordIdentifier}");