[DOCS]: Add license information

[xZero707]

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Describe the need

There is no licensing information available about release binaries. This probably assumes that the license is proprietary.
Specifically, I'm working on an MIT-licensed project that would provide a Docker image with both GitHub CLI and Copilot extension. The repository doesn't include any files; binaries are downloaded from releases, during build time and packaged into the image.
Without knowing the licensing requirements I cannot publish the project.

Version

Relevant terminal output