remove SSL observatory l10n resource
SSL Observatory has been removed from HTTPS Everywhere codebase, ref
https://github.com/EFForg/https-everywhere/pull/18408
so i should
- remove it from transifex
- move it from the translations repo to the attic.
SSL Observatory has been removed from HTTPS Everywhere codebase, ref
https://github.com/EFForg/https-everywhere/pull/18408
so i should