Bad formatting when logging state information

[DomGarguilo]

When an exception occurs when running rwalk, the state information gets logged.

One of the logs is the lastIndexRow which gets printed like this:

lastIndexRow: class org.apache.hadoop.io.Text - ����-T�g����Uj<�s�S

There is some logic to format various Object types before printing them and I'm thinking a case could be added to this section to format the value of lastIndexRow too: https://github.com/apache/accumulo-testing/blob/ae9c46552a661c2dec132d26835cec5dd2ecbf66/src/main/java/org/apache/accumulo/testing/randomwalk/Module.java#L346-L362

Maybe something similar to https://github.com/apache/accumulo/pull/2906 could be done here.