[lldb/test] Fix tests reading log from remote platform instead of host (#183413)
Some tests are using logs to validate that a test behaves correctly
however they used `platform shell cat {log}` to read the logfile.
This doesn't work when running the testsuite against a remote platform
since the logs are saved on the host's filesystem.
This patch addresses those failures by making sure we read the log file
from the host platform.
Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>