build

Bogus safety violation checking if a set is a subset of Nat. #6943

Job	Run time
build-mdbook	5s
docker-tests	21m 38s
compiler-warnings	2m 5s
format-check	3m 42s
integration-tests (ubuntu-latest, oopsla19)	18m 42s
scaladoc-check	2m 55s
unit-tests (ubuntu-latest)	5m 4s
integration-tests (ubuntu-latest, arrays)	7m 57s
integration-tests (macos-latest, oopsla19)	12m 19s
unit-tests (macos-latest)	3m 4s
	1h 17m 31s

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