Github oauth code for private access

 github register a new OAuth application and fetch details of app registered, client ID and secret.

As we can't keep them in source code, we will save them in a file on project root folder/.env.local

.env.local

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REACT_APP_GITHUB_CLIENT_ID='<copied from github app page>'

REACT_APP_GITHUB_CLIENT_SECRET='<copied from github app page>'

So, instead of open request to Github api, use below one.

using ` instead of ' below as ${} is there to expand. 

const res = await axios.get(`https://api.github.com/users?client_id=${process.env.REACT_APP_GITHUB_CLIENT_ID}&client_secret=${process.env.REACT_APP_GITHUB_CLIENT_SECRET}`);