Fix usage of Gazebo plugins as linked libraries on macOS

[traversaro]

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-webservices]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[traversaro]

@conda-forge-admin, please rerender

[Tobias-Fischer]

Should we use a glob instead? Anything with plugin in the name?

[traversaro]

Should we use a glob instead? Anything with plugin in the name?

I think more and less everything in the $PREFIX/lib/gazebo-11/plugins folder has plugin in its name, so we could just iterate on the directory content. However, to reduce the chance of clobbering I would just keep that list, that is the one we actually need for gazebo-ros-plugins.

[Tobias-Fischer]

Great, thanks for the explanation!