Add a license to the repository

I recently came across your project pycon-quantum and I noticed that the repository github.com/ajmalsiddiqui/pycon-quantum currently does not have a license specified.

Why Adding a License is Important?

As [GitHub documents](https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/licensing-a-repository)
>Public repositories on GitHub are often used to share open source software. For your repository to truly be open source, you'll need to license it so that others are free to use, change, and distribute the software.

Would be possible to add a valid license to this repository? Probably something really OpenSource such as the [Apache 2.0 license](https://www.apache.org/licenses/LICENSE-2.0) would fit really well.

Thanks!

Start with the repository root and the GitHub licensing guidance linked in the issue. Confirm which license the maintainers want, then add the corresponding license file; done means the repository displays a valid open-source license.

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