build-unit-test-docker: switch to ubuntu oracular
Ubuntu Oracular is released; switch to it.
As part of this, add systemd-dev to the dependencies in order to solve
the following build failure:
```
openbmc/phosphor-objmgr: Run-time dependency systemd found: NO (tried pkgconfig and cmake)
openbmc/phosphor-objmgr:
openbmc/phosphor-objmgr: meson.build:114:26: ERROR: Dependency "systemd" not found, tried pkgconfig and cmake
```
The systemd.pc file is only available as part of systemd-dev now.
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I6fc4c67c0d5954f47e3752af9b335742901212ac
1 file changed