YAMBi: Remove `shelltest` tag from plugin contract
- infos/provides = storage/yaml
- infos/recommends =
- infos/placements = getstorage
-- infos/status = maintained unittest shelltest preview experimental unfinished nodoc concept discouraged
+- infos/status = maintained unittest preview experimental unfinished nodoc concept discouraged
- infos/metadata =
- infos/description = This storage plugin use a parser generated by Bison to read YAML files
