[tests] change "moul" id in tests

Tests do not pass, because there is another id matching "moul" :

$ silkaj wot moul
|   id | uid    | pubkey                                           | timestamp             |
|------+--------+--------------------------------------------------+-----------------------|
|   00 | moulid | 9Knv36EhWwvV25zz7emUHgV4C99sdJy8mrPXtggMFyBr:8hE | 380083-00000026145B1… |
|   10 | moul   | GfKERHnJTYzKhKUma5h1uWhetbA8yHKymhVH2raf2aCP:J1k | 0-E3B0C44298FC1C149A… |

suggestion : replace "moul" id, with which my friend Mouloud may create a conflict, by Matograine, which will probably not be subject to conflicts.