run-unit-test-docker: Support http_proxy env

If http_proxy env is set, add proxy related env into docker container so
that the unit test could be run in a proxy environment.

This could be useful for repo like bmcweb that downloads extra content
during build and test.

Tested: Verify the bmcweb repo CI could use the proxy to download the
        DSP8010 schema zip.

Signed-off-by: Lei YU <yulei.sh@bytedance.com>
Change-Id: I8970c5eec76adaa096af127c93c409de55221181
1 file changed