[lldb][test][Windows] Fix NonStop tests on case insensitive file systems

On a case insensitive file sytem, the build dir for `test_multiple_c` and
`test_multiple_C` are the same and therefore the log files are in the same
place. This means one tries to clear the log file for the other.

To fix this, make the names unique by adding the meaning of each
protocol packet.

https://sourceware.org/gdb/current/onlinedocs/gdb.html/Packets.html#Packets