test: support https protocol

[supertassu]

Updates the test script to require passing a protocol instead of assuming everything is done over plain http.

[linux-foundation-easycla[bot]]

The committers listed above are authorized under a signed CLA.

• :white_check_mark: login: supertassu / name: Taavi Väänänen (4c85e8d2bd3ed1fc6496dbf1ac364b8fbc640fae)