docs: public void setRdsDbInstanceArns(java.util.Collection<String> rdsDbInstanceArns) {
          if (rdsDbInstanceArns == null) {
              this.rdsDbInstanceArns = null;
              return;
          }
  
          this.rdsDbInstanceArns = new com.amazonaws.internal.SdkInternalList<String>(rdsDbInstanceArns);
      }