docs: public ListSigningCertificatesResult withCertificates(SigningCertificate... certificates) {
          if (this.certificates == null) {
              setCertificates(new com.amazonaws.internal.SdkInternalList<SigningCertificate>(certificates.length));
          }
          for (SigningCertificate ele : certificates) {
              this.certificates.add(ele);
          }
          return this;
      }