Ability for Users to parameterize how the UnexpectedRowsExpectation appears on the DataDocs

[Erua-chijioke]

Is your feature request related to a problem? Please describe.
Currently on V1.3.2 and noticed that if one creates a custom expectation using the class UnexpectedRowsExpectation, The datadocs shows the number of unexpected row as seen in the image below. It does not show the content in the actual rows returned,

Describe the solution you'd like
Parameterize how the results show up in the datadocs such that if a user want to see the actual unexpected rows in the datadocs, they can and if they don't want it shown, they can also opt for that. Parameterizing is the best approach because showing all the unexpected rows can be an information overload to some users.