[fix] BMA: optimize `/tx/requirements/:search` for Duniter 1.8 - close #1439

app/lib/dal/fileDAL.ts

app/lib/dal/indexDAL/abstract/IIndexDAO.ts

app/lib/dal/indexDAL/leveldb/LevelDBIindex.ts

app/lib/dal/indexDAL/sqlite/SqliteIIndex.ts

app/lib/dal/sqliteDAL/IdentityDAL.ts

app/modules/bma/lib/controllers/wot.ts

app/modules/bma/lib/parameters.ts

app/service/IdentityService.ts

test/integration/identity/identity-test.ts