Add proposal-upsert methods to lib.esnext.collection #35303

Job	Run time
misc	28s
knip	33s
package-size	1m 25s
baselines	8m 43s
lint	56s
coverage	10m 4s
smoke	55s
Test Node 24 on windows-latest	10m 40s
typecheck	43s
self-check	57s
Test Node 24 on ubuntu-latest	8m 16s
browser-integration	1m 28s
Test Node 14 on ubuntu-latest	12m 0s
format	24s
Test Node 14 on windows-latest	14m 29s
Test Node lts/* on ubuntu-latest with --no-bundle	10m 28s
required	2s
	1h 22m 31s

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