[lldb][NFC] Rewrite TestQuoting

TestQuoting's different test methods all build their own test binaries but
we can just reuse the same test binary by merging all asserts into one method.
This reduces the test runtime from 8 seconds to 4 seconds on my machine.
This also removes the ability to have partial failures in this test, but given
how rarely this code is touched this seems like a fair tradeoff (and we will be
able to re-add this feature once we updated our test framework).

Some other small changes:
  * Fixed that we cleanup "stdout.txt" instead of "output.txt" in the cleanup.
  * Fixed some formatting issues.
  * Call `build` instead of directly calling `buildDefault`.