code: public SimplifySpanBuild appendToFirst(String text) {
          if (TextUtils.isEmpty(text)) return this;
  
          mNormalSizeText.append(text);
          mBeforeStringBuilder.append(text);
          return this;
      }
docs: append normal text to first (Behind the existing BeforeContent)
  
  @param text normal text
  @return SimplifySpanBuild