bugfix: validation/aggregating/plots/SALVIAS/bien3_validations_salvias_db_original.VegCore.sql: can't double-JOIN like in MySQL (`JOIN a JOIN b ON a_conds AND b_conds`), so split double-JOIN into two JOINs w/ own ON clauses
bugfix: validation/aggregating/plots/SALVIAS/bien3_validations_salvias_db_original.VegCore.sql: can't double-JOIN like in MySQL (`JOIN a JOIN b ON a_conds AND b_conds`), so split double-JOIN into two JOINs w/ own ON clauses