David Spickett fd8b84ea0f [lldb][test] Skip beginning/end of file tests on Windows
Added in https://github.com/llvm/llvm-project/pull/137515,
as the source uses unistd.h which isn't present there.

| C:\Users\tcwg\llvm-worker\lldb-aarch64-windows\llvm-project\lldb\test\Shell\Commands/Inputs/sigchld.c:4:10: fatal error: 'unistd.h' file not found
|     4 | #include <unistd.h>
|       |          ^~~~~~~~~~
| 1 error generated.
2025-05-09 10:31:17 +00:00
..