Add run_exports

[traversaro]

graphviz is a C shared library that was also subject to migrations (see https://github.com/conda-forge/conda-forge-pinning-feedstock/pull/3457/files), so it make sense to make sure that downstream packages depend correctly on it, to avoid problems such as https://github.com/conda-forge/gazebo-feedstock/issues/159 .

This PR also install libwebp-base on Windows, as without it the Windows build was failing.

Checklist

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

[conda-forge-linter]

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]

Looks like this needs webp in the dependencies @traversaro

[conda-forge-webservices[bot]]

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]

Superseded by https://github.com/conda-forge/graphviz-feedstock/pull/117 .

Edit (by jakirkham): To fix link