Add --test option in man page

[njourdane]

Describe the bug
The --test CLI option is not displayed in the man page.

To Reproduce

man marked

This appends in last version and simple to verify by looking at the man files.

Expected behavior

The --test CLI option should be displayed in the man page, since it is a valid option in the marked binary.

[x13machine]

I think, this should be closed

[styfle]

Fixed in #1442