Utilize jscodeshift CLI results output

[gitKrystan]

Fixes #523

Previous iterations of this codemod did not take full advantage of jscodeshift's (undocumented AFAICT) results API.

Thus, a user might see:

 All done. 
 Results: 
 0 errors
 58 unmodified
 0 skipped
 0 ok
 Time elapsed: 3.029seconds 

when their codemods.log file had multiple entries like this:

2023-03-14T11:25:08.799Z [error] [addon/controllers/foo.js]: 
FAILURE 
Validation errors for class 'FooController': 
	[actions]: Transform not supported - [destroy]: action name matches one of the lifecycle hooks. 
Rename and try again. See https://github.com/scalvert/ember-native-class-codemod/issues/34 for more details

This discrepancy can be pretty confusing for users.

I did some code-reading and found that jscodeshift checks the output of the transform function and sorts the transform attempt into its corresponding results category based on the following:

Result	How-to	Meaning
errors	throw	we attempted to transform but encountered an error
unmodified	return string (unchanged)	we attempted to transform but it was unnecessary
skipped	return undefined	we did not attempt to transform
ok	return string (changed)	we successfully transformed

While the changes to make this happen for this codemod were trivial, I found that neither codemod-cli nor jscodeshift's testing helpers expect the transform to throw, so I had to re-write the testing helpers and get a little creative to expect errors and error messages. Thus, this PR is mostly testing changes.

Additionally, due to the nature of throwing to give an errors result, I had to remove the partialTransforms functionality. This means that the codemod will fail for the file if any object within the file fails. This is standard for jscodeshift codemods apparently and was the standard for this codemod until very recently when I changed it thinking it would be helpful. It turns out not to be helpful.