This won’t likely be specific to anything in MSFS, but will be loaded into all processes on the system since you have it installed.
An mdns resolver like Bonjour provides network domain name resolution for “.local” addresses to computers on the local network advertising their names via local broadcast packets.
I presume that like similar systems on Linux it works by loading the library into all programs via some system hook so that when doing a lookup (eg to get 1.2.3.4 from “some-server.microsoft.com”) it knows how to look up “.local” addresses.
(This shouldn’t actually affect anything, as MSFS doesn’t let you input arbitrary URLs to download from, much less random computers on your network. 
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