message: fix(core): Remove optional chaining usage
  Remove optional chaining usage. This should mean we don't import the
  optional chaining polyfill into the browser bundle any more.
diff: @@ -291,7 +291,10 @@ export abstract class BaseClient<O extends ClientOptions> implements Client<O> {
  for (const attachment of hint.attachments || []) {
  env = addItemToEnvelope(
  env,
  - createAttachmentEnvelopeItem(attachment, this._options.transportOptions?.textEncoder),
  + createAttachmentEnvelopeItem(
  + attachment,
  + this._options.transportOptions && this._options.transportOptions.textEncoder,
  + ),
  );
  }
  