Add Docusaurus site source

[ptgott]

No description provided.

[aws-amplify-us-west-2]

This pull request is automatically being deployed by Amplify Hosting (learn more).

Access this pull request here: https://pr-1.d2mrezcly5gcqm.amplifyapp.com

[taraspos]

Update favicon to use new logo:

• https://github.com/gravitational/docs-website/blob/7f3d418020dae86574a25dd25bd4b7bd3ed6cb41/static/favicon.svg

[ptgott]

Update favicon to use new logo:

• https://github.com/gravitational/docs-website/blob/7f3d418020dae86574a25dd25bd4b7bd3ed6cb41/static/favicon.svg

Fixed in ecc8d3f

[ptgott]

@mmcallister Are you able to review this one so we can merge the Docusaurus source?

[taraspos]

@ptgott seems like it won't work unless we copy following GHA:

• https://github.com/gravitational/docs/blob/main/.github/workflows/codeql.yml
• https://github.com/gravitational/docs/blob/main/.github/workflows/dependency-review.yaml

[github-advanced-security]

This pull request sets up GitHub code scanning for this repository. Once the scans have completed and the checks have passed, the analysis results for this pull request branch will appear on this overview. Once you merge this pull request, the 'Security' tab will show more code scanning analysis results (for example, for the default branch). Depending on your configuration and choice of analysis tool, future pull requests will be annotated with code scanning analysis results. For more information about GitHub code scanning, check out the documentation.