```
> warnings.warn(f"Error reporting testrun: {e}: {e.read()}")
E AttributeError: 'URLError' object has no attribute 'read'
```
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Code using `CI_SERVER` was added recently to track something. It
attempts to short-cut if `CI_SERVER` is not set, but on gitlab it
is set to `yes`. https://docs.gitlab.com/ee/ci/variables/
Instead use `CI_SERVER_URL`, maybe that is what is intended?
