message: use isNonMetalBond
diff: @@ -98,7 +98,7 @@ export class Mol2Encoder extends LigandEncoder {
  let result = iter.next();
  while (!result.done) {
  const [k, v] = result.value;
  - if (NON_METAL_ATOMS.some(a => k.startsWith(a))) {
  + if (this.isNonMetalBond(k)) {
  ret.set(k, v);
  }
  result = iter.next();
  