By default, the child processes spawned by exec process will inherit standard
io file descriptors. The shim server creates a pipe as data channel. Both exec
process and its children write data into the write end of the pipe. And the
shim server will read data from the pipe. If the write end is still open, the
shim server will continue to wait for data from pipe.
So, if the exec command is like `bash -c "sleep 365d &"`, the exec process is
bash and quit after create `sleep 365d`. But the `sleep 365d` will hold the
write end of the pipe for a year! It doesn't make senses that CRI plugin
should wait for it.
For this case, we should use timeout to drain exec process's io instead of
waiting for it.
Fixes: #7802
Signed-off-by: Wei Fu <fuweid89@gmail.com>
