[lldbsuite] Make the names of test classes unique

Summary:
If the names are not unique, the tests overwrite each other's results and logs. This also causes failures on platforms where the files are locked for writing.

The names of the class/test pairs *have to* always be unique. The easiest way to achieve that is to name each class differently (usually the same as the file name).

Reviewers: jasonmolenda, asmith

Subscribers: clayborg, nemanjai, kbarton, lldb-commits

Differential Revision: https://reviews.llvm.org/D53297

llvm-svn: 344547