bisect-kit: handle symbolic link case when removing session

BUG=b:183686737
TEST=manually

Change-Id: I891ec71f927479321ccfbc1492913df12154f91d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/bisect-kit/+/2874817
Tested-by: Zheng-Jie Chang <zjchang@chromium.org>
Auto-Submit: Zheng-Jie Chang <zjchang@chromium.org>
Commit-Queue: Kuang-che Wu <kcwu@chromium.org>
Reviewed-by: Kuang-che Wu <kcwu@chromium.org>
1 file changed