Working link: https://www.acquisition.gov/dfars/252.239-7018-supply-chain-...

HN separates trailing dots from URLs, so that you can have working URLs at the end of a sentence. Hence you have to percent-encode trailing dots if they are a necessary part of the actual URL. (Same for some other punctuation characters, probably.)

This behavior is common for auto-hyperlinking of URLs in running text, so it’s bad practice to have such URLs.