ReadMe.md(Roadmap): update threshold sigs info #3867

Job	Run time
macOS--dotnet6-and-mono	14m 58s
windows--dotnet6-and-legacyFramework	5m 55s
macOS--mono-only	10m 34s
windows--dotnet6-only	5m 54s
macOS--dotnet6-only	4m 53s
windows--legacyFramework-only	21m 42s
linux-github--dotnet-and-mono	3m 48s
linux-vanilla--newmono-only	8m 19s
linux-vanilla--stockdotnet6-and-newmono	5m 50s
linux-vanilla--stockdotnet6-and-stockmono	6m 26s
linux-github--dotnet-and-newmono	7m 17s
linux-vanilla--stockdotnet6-only	5m 16s
linux-vanilla--stockmono-only	5m 27s
conventions	2m 36s
snap_pkg	6m 25s
snap_pkg_beta	7m 6s
	2h 2m 26s

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