Update msal-common readme
Update msal-common readme

AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js,AzureAD/microsoft-authentication-library-for-js