AIRO-1690 Removing option to convert all meshColliders to non convex type meshes

Proposed change(s)

Removing a button in the inspector window of the UrdfRobot script that allows the user to toggle "is convex" option for colliders. Non-convex meshes are incompatible with ArticulationBodies, which is the only supported Physics entity in Unity, hence making the functionality unuseful.

Useful links (GitHub issues, JIRA tickets, forum threads, etc.)

https://github.com/Unity-Technologies/URDF-Importer/issues/171

Types of change(s)

[ ] Bug fix
[ ] New feature
[x] Code refactor
[ ] Documentation update
[ ] Other (please describe)

Testing and Verification

Please describe the tests that you ran to verify your changes. Please also provide instructions, ROS packages, and Unity project files as appropriate so we can reproduce the test environment.

Test Configuration:

Unity Version: [e.g. Unity 2020.2.0f1]
Unity machine OS + version: [e.g. Windows 10]
ROS machine OS + version: [e.g. Ubuntu 18.04, ROS Noetic]
ROS–Unity communication: [e.g. Docker]

Checklist

[x] Ensured this PR is up-to-date with the dev branch
[x] Created this PR to target the dev branch
[ ] Followed the style guidelines as described in the Contribution Guidelines
[ ] Added tests that prove my fix is effective or that my feature works
[ ] Increased the test coverage criteria by 3%
[x] Updated the Changelog and described changes in the Unreleased section
[ ] Updated the documentation as appropriate

Unity-Technologies / URDF-Importer

AIRO-1690 Removing option to convert all meshColliders to non convex type meshes #183