Clearer errors if we find a class without a known ending.

src/Parser/Parser.cpp

@@ -137,7 +137,7 @@ namespace MalachScript::Parser {
                 }
                 break;
             }
-            default: return false;
+            default: logError(DiagnosticType::UnexpectedToken, current->GetSpan()); return false;
         }
         out = new ParsedClassStatement(TextSpan(start, current->GetSpan().GetEnd()), classAttr, identifier, inherits,
                                        body);