[selection-api] Fix capitalization of GitHub (#44)

This is how the company capitalizes the product name.

(P.S.: Hi @rniwa!)
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/selection-api/pull/44

-- Commit Summary --

  * Fix capitalization of GitHub

-- File Changes --

    M index.html (2)

-- Patch Links --

https://github.com/w3c/selection-api/pull/44.patch
https://github.com/w3c/selection-api/pull/44.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/selection-api/pull/44