Add new variant for tbb==2021.*

[diegoferigo]

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.

[diegoferigo]

@conda-forge-admin, please rerender

[conda-forge-admin]

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/recipe.yaml) and found it was in an excellent condition.

I do have some suggestions for making it better though...

For recipe/recipe.yaml:

• ℹ️ noarch: python recipes should usually follow the syntax in our documentation for specifying the Python version.
  • For the tests[].python.python_version or tests[].requirements.run section of coacd output, you should usually use the pin python_version: ${{ python_min }}.* or python ${{ python_min }}.* for the python_version or python entry.
  • If the package requires a newer Python version than the currently supported minimum version on conda-forge, you can override the python_min variable by adding a Jinja2 set statement at the top of your recipe (or using an equivalent context variable for v1 recipes).

_{This message was generated by GitHub Actions workflow run https://github.com/conda-forge/conda-forge-webservices/actions/runs/23734657274. Examine the logs at this URL for more detail.}

[diegoferigo]

xref

• Incorrect symbols when loading library. openusd-feedstock#9
• [Proposal] Improvements to support distribution and third-party packaging isaac-sim/IsaacLab#5084

[conda-forge-admin]

Hi! This is the friendly conda-forge automerge bot!

I considered the following status checks when analyzing this PR:

• linter: passed
• azure: passed
• github-actions: passed

Thus the PR was passing and merged! Have a great day!