Update the "Installing on Microsoft Azure" article

[skoshelev]

After the release of version 4.70, update the article https://docs.nopcommerce.com/en/installation-and-upgrading/installing-nopcommerce/installing-on-microsoft-azure.html. Need to add recommendations for adding user agent for Azure Traffic Manager and Azure AppService AlwaysOn as crawlers into the additional.crawlers.xml file. See ditails on this PR