Update Group-Free-3D and FCOS3D bibtex

[Tai-Wang]

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Motivation

Update Group-Free-3D and FCOS3D bibtex.

Modification

Update Group-Free-3D and FCOS3D bibtex in the config README and master README.

BC-breaking (Optional)

No.

Checklist

1. Pre-commit or other linting tools are used to fix the potential lint issues.
2. The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
3. If the modification has potential influence on downstream projects, this PR should be tested with downstream projects.
4. The documentation has been modified accordingly, like docstring or example tutorials.