Show logo for mobile views in create-react-app.dev

[GrooChu]

This PR fixes issue #7517
Create react is not being displayed in create-react-app.dev page because docusaurus by default hides the logo for mobile view. Fix here involves displaying the the logo for all the resolutions. https://github.com/facebook/docusaurus/blob/bd72aacfe85c2e239d6d92486850b5a229cda836/packages/docusaurus-1.x/lib/static/css/main.css#L592

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[iansu]

Thanks!