code: static @Nonnull String removeQuote( @Nonnull String str ) {
          if( str.length() > 1 ) {
              char ch = str.charAt( 0 );
              if( ch == '\'' || ch == '\"' ) {
                  if( str.charAt( str.length() - 1 ) == ch ) {
                      return str.substring( 1, str.length() - 1 );
                  }
              }
          }
          return str;
      }
docs: Remove a quote if exists.
  
  @param str a string
  @return the str without quotes