Backend(,Tests): stop using binary serialization #3024

Job	Run time
macOS--dotnet6-and-mono	5m 3s
macOS--mono-only	5m 15s
windows--dotnet6-and-legacyFramework	3m 43s
linux-github--dotnet-and-mono	2m 0s
linux-github--dotnet-and-newmono	2m 45s
linux-vanilla--newmono-only	4m 39s
linux-vanilla--stockdotnet6-and-newmono	2m 56s
linux-vanilla--stockdotnet6-and-stockmono	2m 43s
linux-vanilla--stockdotnet6-only	2m 8s
linux-vanilla--stockmono-only	3m 1s
macOS--dotnet6-only	2m 15s
windows--dotnet6-only	3m 32s
windows--legacyFramework-only	10m 53s
conventions	0s
snap_pkg	0s
snap_pkg_beta	0s
	50m 53s

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