Update error status bar when file is missing

[sssoleileraaa]

Description

Currently refreshing the file object in the session after we update it in Controller::downloaded_file_exists causes the error status message to be cleared, but we need a way to show the error message "File does not exist in the data directory. Please try re-downloading." without it disappearing right away.

[eloquence]

From 2022-08-22 review with @nathandyer @cfm @gonzalo-bulnes @eloquence:

• We probably want to revisit the purpose of this error message.
• Assuming we want to keep the error message, this issue suggests that the current behavior is that the error message may disappear right away, so labeling as "needs reproducing" for now to better understand if this is a bug. Keeping open.