DeepChem Updates of March (Week 1), 2024

Here is a quick summary of merged pull requests for DeepChem during the first week of March:
1. Fix failing torch tests due to missing pydantic package: This PR fixes a failing Torch test.
2. Fix bugs on ligand handling and pdbqt ligand support: This PR fixes issues with pose_generation DeepChem’s support for Vina, specifically incorrect changes to atom names and problem in processing ligand files.
3. Pytest Fix (temporary): This PR temporarily fixes failing pytests used for testing DeepChem code.
4. Remove invalid line in hf_models.py: This PR removes an invalid line in hf_models.py because HuggingFace models return output of type dict and not index.
5. Reduce import warnings: This PR reduces import warnings in DeepChem by changing how missing dependencies like pysam are reported and includes a minor update to the bace-classification documentation.
6. Added Cell counting Tutorial: This PR adds Cell Counting Tutorial to DeepChem.
7. DFT Part-3: This PR fixes issues with DFT.
8. Molgan GPU Support: This PR adds MolGan GPU support.