Fix error display when an MPI process fails

Non backtrace errors (normal errors for instance) were silent.

src/language/PugsParser.cpp

@@ -133,9 +133,9 @@ parser(const std::string& filename)
       std::exit(1);
     }
     catch (const IExitError& e) {
+      // Each failing process must write
+      std::cerr.clear();
       std::cerr << ASTBacktrace::getInstance().errorMessageAt(e.what()) << '\n';
-
-      finalize();
       std::exit(1);
     }
   } else {