Can't compile when including gz/sim.hh, not enough include paths exported

[scpeters]

Environment

• OS Version: Ubuntu 20.04, 22.04, macOS
• Source or binary build? source build of gz-sim7, tested with 4c57ea4

Description

• Expected behavior: I should be able to target_link_libraries against gz-sim7::core and #include <gz/sim.hh> and build successfully
• Actual behavior: it fails to find some referenced header files

Steps to reproduce

1. Checkout 4c57ea4
2. Configure using cmake
3. Build the INTEGRATION_include_sim_hh target
4. Observer failure to build (following log from local test on macOS):

[100%] Building CXX object test/integration/CMakeFiles/INTEGRATION_include_sim_hh.dir/include_sim_hh.cc.o
In file included from test/integration/include_sim_hh.cc:20:
In file included from build/include/gz/sim.hh:144:
include/gz/sim/physics/Events.hh:24:10: fatal error: 'gz/physics/ContactProperties.hh' file not found
#include <gz/physics/ContactProperties.hh>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

Output

See Github Actions workflow output: https://github.com/gazebosim/gz-sim/actions/runs/4794159738

[scpeters]

I believe this is causing ABI checker builds targeting the ign-gazebo3 branch to fail