The patch set [1] added a general lib.sh in net selftests, and converted
several test scripts to source the lib.sh.
unicast_extensions.sh (converted in [1]) and pmtu.sh (converted in [2])
have a /bin/sh shebang which may point to various shells in different
distributions, but "source" is only available in some of them. For
example, "source" is a built-it function in bash, but it cannot be
used in dash.
Refer to other scripts that were converted together, simply change the
shebang to bash to fix the following issues when the default /bin/sh
points to other shells.
Link: https://lore.kernel.org/all/20231202020110.362433-1-liuhangbin@xxxxxxxxx/ [1]
Link: https://lore.kernel.org/all/20231219094856.1740079-1-liuhangbin@xxxxxxxxx/ [2]
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Signed-off-by: Yujie Liu <yujie.liu@xxxxxxxxx>