journal: do not pass in repolookuperror string to template (BC)

This doesn't look like data, but a warning message.

hgext/journal.py

@@ -514,7 +514,7 b' def journal(ui, repo, *args, **opts):'
                     ctx = repo[hash]
                     displayer.show(ctx)
                 except error.RepoLookupError as e:
-                    fm.write('repolookuperror', "%s\n\n", pycompat.bytestr(e))
+                    fm.plain("%s\n\n" % pycompat.bytestr(e))
             displayer.close()
 
     fm.end()