Remove Code Upload/Docker Image Submission from CLI Docs and Add Reference Note in Main

[RishabhJain2018]

Description:

The current EvalAI CLI documentation at https://cli.eval.ai/ contains outdated instructions for code upload and docker image-based submissions (e.g., evalai push). These are no longer actively supported.

This issue proposes cleaning up the CLI docs and updating the main documentation accordingly — while ensuring support for large submission uploads remains intact.

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🧹 Tasks

1. Update CLI Documentation

• Remove all references and sections related to:

  • evalai push
  • Code upload
  • Docker image-based submission modes

• Do not remove or modify any commands related to large file submissions (e.g., multipart uploads or evalai upload with --large flag)

• Add a note in the CLI readme if needed to clarify the distinction

2. Update Main EvalAI Documentation

• Under a new heading (e.g., "Deprecated Submission Modes"), mention that:

  • Docker/code upload submissions are deprecated
  • Users should not use the evalai push flow

• Link to the CLI documentation for historical reference, if necessary