usage--
./main <Download_location> <file1URl> <file2Url> ...
fileURL example--
https://nextjs.org/static/blog/next-14/twitter-card.png
https://download.logo.wine/logo/Node.js/Node.js-Logo.wine.png
https://www.goodworklabs.com/wp-content/uploads/2016/10/reactjs.png
downloaded file name will be the term after the last "/"
example for the given URLs--
twitter-card.png
Node.js-Logo.wine. png
reactjs.png
semaphore is used so only a fixed number (MAX_CONCURRENT_DOWNLOADS) of files can be downloaded at a time
