This fix tries to address the issue raised in #34208 where
in Dockerfile an `ADD` followed by an url without any sub path
will cause an error.
The issue is because the temporary filename relies on the sub path.
An integration test has been added.
This fix fixes#34208.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Upstream-commit: bea0a072d86604071c99e9b6989b19ca4fe22032
Component: engine
ac38bbaf63