Deprecate downlevelIteration #35186

Job	Run time
format	28s
knip	34s
typecheck	41s
browser-integration	1m 48s
lint	56s
coverage	10m 43s
smoke	55s
package-size	1m 33s
baselines	8m 58s
self-check	59s
misc	33s
Test Node 24 on windows-latest	10m 14s
Test Node 24 on macos-latest	15m 42s
Test Node 20 on ubuntu-latest	10m 21s
Test Node 22 on windows-latest	11m 57s
Test Node 22 on ubuntu-latest	9m 51s
Test Node 24 on ubuntu-latest	8m 8s
Test Node 18 on ubuntu-latest	11m 35s
Test Node 14 on ubuntu-latest	11m 35s
Test Node 20 on windows-latest	12m 55s
Test Node 16 on windows-latest	13m 40s
Test Node 18 on windows-latest	13m 49s
Test Node 14 on windows-latest	14m 22s
Test Node lts/* on ubuntu-latest with --no-bundle	10m 27s
Test Node 16 on ubuntu-latest	11m 26s
Test Node 16 on macos-latest	12m 34s
required	3s
	3h 26m 47s

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