Implement functions to eliminate ambient noise

[abearab]

• [x] Add scar into the conda environment file
• [x] Write a function to remove ambient noise for given AnnData object(s)
• [x] ~Add CellBender into the conda environment file~

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Reference:

• Probabilistic modeling of ambient noise in single-cell omics data. bioRxiv (2022)

  • https://github.com/Novartis/scar
  • https://scar-tutorials.readthedocs.io/en/main/
  • https://docs.scvi-tools.org/en/stable/user_guide/models/scar.html#ref1

• CellBender removes technical artifacts from single-cell RNA sequencing data. Nat Methods (2023).