Correctly handle UI hierarchy without a camera #40067

Job	Run time
build (windows-latest)	1m 27s
check-doc	2m 1s
build (ubuntu-latest)	1m 28s
ci	1m 28s
miri	7m 12s
build (macos-latest)	1m 43s
run-examples-macos-metal	1m 43s
toml	2m 3s
check-bevy-internal-imports	3s
typos	7s
check-cfg	56s
check-missing-examples-in-docs	33s
check-missing-features-in-docs	34s
markdownlint	1m 10s
check-compiles	0s
build-wasm-atomics	0s
msrv	0s
build-wasm	0s
	22m 28s

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