Check rows.Err() after the timeline scan loop (#27)

internal/api/incidents.go

@@ -189,6 +189,10 @@ func handleIncidentTimeline(db *sql.DB) http.HandlerFunc {
 			e.CreatedAt = time.Unix(ts, 0).UTC()
 			events = append(events, e)
 		}
+		if err := rows.Err(); err != nil {
+			respond(w, http.StatusInternalServerError, errResp("internal error"))
+			return
+		}
 		respond(w, http.StatusOK, events)
 	}
 }