Add TaskResult.foldResult #782

Job	Run time
build-devcontainer	9m 38s
dotnet-build (Debug, ubuntu-latest)	2m 54s
fable-python-build (ubuntu-latest, 3.10)	2m 43s
dotnet-build (Debug, windows-latest)	5m 28s
fable-npm-build (ubuntu-latest, 18)	1m 57s
fable-python-build (ubuntu-latest, 3.11)	2m 48s
dotnet-build (Debug, macOS-latest)	8m 17s
fable-npm-build (ubuntu-latest, 20)	1m 59s
fable-python-build (ubuntu-latest, 3.12)	2m 54s
dotnet-build (Release, ubuntu-latest)	2m 57s
fable-npm-build (ubuntu-latest, latest)	1m 57s
fable-python-build (windows-latest, 3.10)	3m 47s
dotnet-build (Release, windows-latest)	4m 8s
fable-npm-build (windows-latest, 18)	5m 56s
fable-python-build (windows-latest, 3.11)	5m 38s
dotnet-build (Release, macOS-latest)	4m 18s
fable-npm-build (windows-latest, 20)	5m 47s
fable-python-build (windows-latest, 3.12)	4m 2s
fable-npm-build (windows-latest, latest)	6m 7s
fable-python-build (macOS-latest, 3.10)	4m 24s
fable-npm-build (macOS-latest, 18)	2m 53s
fable-python-build (macOS-latest, 3.11)	3m 43s
fable-npm-build (macOS-latest, 20)	4m 1s
fable-python-build (macOS-latest, 3.12)	4m 7s
fable-npm-build (macOS-latest, latest)	4m 5s
	1h 46m 28s

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