Local storage should not store files as executable (#22162) (#22163)
Backport #22162
The PR #21198 introduced a probable security vulnerability which
resulted in making all storage files be marked as executable.
This PR ensures that these are forcibly marked as non-executable.
Fix #22161
Signed-off-by: Andrew Thornton <art27@cantab.net>
Signed-off-by: Andrew Thornton <art27@cantab.net>