In some cases, the LLDB test suite will be run on a built framework with no sources coming along. In those cases, we want to skip the SB API test case. Add a marker for that, and apply it

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@219146 91177308-0d34-0410-b5e6-96231b3b80d8