Goal 'aggregate-download-licenses' doesn't check <licensesConfigFile> for valid <url> elements

[duracotton]

If I specify the plugin to use my "licensesConfigFile" where I declare some licenses manually but accidentally insert some invalid "url" value to a license text, the plugin is not checking if those licenses can actually be downloaded.
It just skips the download of invalid URLs to the "licensesOutputDirectory" but still puts the "url" values into the resulting "licensesOutputFile" and remains silent that it wasn't able to download the license text.