Tests

Support arbitrary messaging from external loaders #945

Job	Run time
osx	5m 43s
linux (swift:5.8-bionic)	4m 11s
linux (swift:5.8-focal)	5m 45s
linux (swift:5.8-jammy)	3m 51s
linux (swift:5.8-amazonlinux2)	5m 17s
linux (swift:5.9-focal)	5m 18s
linux (swift:5.9-jammy)	4m 2s
linux (swift:5.9-amazonlinux2)	4m 9s
linux (swift:5.10-focal)	3m 51s
linux (swift:5.10-jammy)	4m 6s
linux (swift:5.10-amazonlinux2)	4m 13s
linux (swiftlang/swift:nightly-bionic)	2m 48s
linux (swiftlang/swift:nightly-focal)	4m 12s
linux (swiftlang/swift:nightly-jammy)	4m 6s
linux (swiftlang/swift:nightly-amazonlinux2)	4m 31s
	1h 6m 3s

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