[SECURITY] Fedora 34 Update: libmicrohttpd-0.9.73-1.fc34

GNU libmicrohttpd is a small C library that is supposed to make it easy to run an HTTP server as part of another application. Key features that distinguish libmicrohttpd from other projects are: * C library: fast and small * API is simple, expressive and fully reentrant * Implementation is http 1.1 compliant * HTTP server can listen on multiple ports * Support for IPv6 * Support for incremental processing of POST data * Creates binary of only 25k (for now) * Three different threading models