selftests: rds: move include.sh to TEST_FILES

selftests: rds: move include.sh to TEST_FILES

The include.sh file is generated for inclusion and should not be executable.
Otherwise, it will be added to kselftest-list.txt. Additionally, add the
executable bit for test.py at the same time to ensure proper functionality.

Fixes: 3ade6ce1255e ("selftests: rds: add testing infrastructure")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/20240927041349.81216-1-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>