Prevent detection of hidden file by FileObserver

Description

Fix issue 5373 by preventing detection of hidden files (starting with '.') and cleaning database at boot if there is an update of eDrive:

• remove entries for hidden files introduced in previous version
• cleaning codes

Issue(s)

https://gitlab.e.foundation/e/backlog/-/issues/5373

Check list

• Self review
• Test procedure explained
• Tested on fresh install
• Tested applied as an update
• License
• Internal documentation
• User documentation