Add AWS S3 dependencies to environment.yml

[0x2b3bfa0]

• Useful for Usage with AWS S3 and Ray #59 because it's harder to install them otherwise
• Doesn't align with the project's choice of leaving cloud-specific dependencies up to users

datacomp/README.md

Line 38 in fa9d766

If using cloud storage services (e.g. AWS S3), you'll need to install additional dependencies (e.g. `pip install 'cloudpathlib[s3]'`).

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@Vaishaal & @rom1504, ping 🛎️

[Vaishaal]

This looks good to me!