RemoveSwitchMutator: print case's id and not order number alone

[rnveach]

Identified at checkstyle/checkstyle#12318 (comment),

It was not clear that the case number being reported by RemoveSwitchMutator is not always the same order as in the source. I understand pitest goes against the bytecode, but I would think a normal person would assume they would be the same unless they work with the byecode a lot.

My suggestion is to add the case number with the integer value of the switch in the description. I contemplate removing the order number all together, but as long as the description is made a bit clearer, I think it is ok. If the case order could be reversed back to the source order, that would also be acceptable, but I assume that may be too complex while the number should be directly available from the bytecode.

So a case like:

67: 140 // 3

Would be reported like:

<description>RemoveSwitch 3 mutation with case value of 67</description> 

Instead of:

<description>RemoveSwitch 3 mutation</description> 

[hcoles]

@rnveach This will be a little confusing for string switches, but I agree it would be an improvement the rest of the time and shouldn't be too hard to implement.