Add package.xml

[azeey]

🎉 New feature

Summary

Add package.xml based on dependencies found in .github/ci/packages.

This is to test out using vendor packages to provide Gazebo packages to ROS users (see gazebo-tooling/release-tools#1117).

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.32%. Comparing base (92e02c3) to head (b800913).
Report is 13 commits behind head on gz-physics7.

❗ Current head b800913 differs from pull request most recent head df390df. Consider uploading reports for the commit df390df to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##           gz-physics7     #608   +/-   ##
============================================
  Coverage        78.32%   78.32%           
============================================
  Files              140      140           
  Lines             8069     8069           
============================================
  Hits              6320     6320           
  Misses            1749     1749           

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[scpeters]

I know dartsim uses this name in its package.xml file, but I had added a colcon.pkg file to change its package name for colcon's purposes to DART so that colcon-cmake would recognize find_package(DART) (see dartsim/dart#1389)

I haven't yet tried to build a workspace with gz-physics, dartsim, bullet and ODE, and we don't need to block on this, but I'm not sure building all those from source in the same workspace will work properly in this current form

[azeey]

You're right. I used colcon graph and saw that gz-physics didn't have a dependency on DART, so I've changed it in df390df

Before

DART            +
gz-cmake3        +********* *****
gz-tools2         +  * ***..*****
gz-utils2          +***.******.*.
gz-math7            + ***********
gz-plugin2           +    ** *.**
gz-common5            +  *** ****
gz-msgs10              + *  *****
sdformat14              + *   ***
gz-fuel_tools9           +     *.
gz-physics7               +    **
gz-rendering8              + ****
gz-transport13              +****
gz-gui8                      + **
gz-sensors8                   +**
gz-sim8                        +*
gz-launch7                      +

After

DART            +         *    ..
gz-cmake3        +********* *****
gz-tools2         +  * ***..*****
gz-utils2          +***.******.*.
gz-math7            + ***********
gz-plugin2           +    ** *.**
gz-common5            +  *** ****
gz-msgs10              + *  *****
sdformat14              + *   ***
gz-fuel_tools9           +     *.
gz-physics7               +    **
gz-rendering8              + ****
gz-transport13              +****
gz-gui8                      + **
gz-sensors8                   +**
gz-sim8                        +*
gz-launch7                      +