Fixed DB seeder to truncate the asset_maintenances table

This wouldn’t have affected anything in production, but could cause some weird behavior if re-seeding often, since the suppliers table gets stomped on but the old maintenances remained, leaving ghost entries and associating the wrong (old, now defunct) supplier with the maintenance as new supplier IDs get generated.

database/seeds/DatabaseSeeder.php

@@ -48,6 +48,7 @@ class DatabaseSeeder extends Seeder
         Model::reguard();
 
         DB::table('imports')->truncate();
+        DB::table('asset_maintenances')->truncate();
 
     }
 }