Fixing compass asset load in standalone builds

[Chootin]

I confirmed the previous version of the code would not work in Unity version 2021.2.18f1 - the default would end up being used instead.

Proposed change(s)

Loading the resources asset with the name rather than the name and file extension.

Types of change(s)

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

Testing and Verification

Created a script which would move an asset when it receives a pose message from ROS. I performed the test in the editor and noted a different result from the build. After connecting a debugger it was apparent the asset wasn't being loaded.

Test Configuration:

• Unity Version: Unity 2021.2.18f1
• Unity machine OS + version: Ubuntu 18.04
• ROS machine OS + version: Ubuntu 18.04, ROS Melodic
• ROS–Unity communication: Local

Checklist

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

Other comments

[unity-cla-assistant]

All committers have signed the CLA.