docs: release notes for the v21.0.0-rc.5 release #10026

Job	Run time
build-e2e-windows-subset	2m 45s
analyze	5s
lint	2m 20s
build	2m 9s
test	3m 32s
e2e (ubuntu-latest, 22, npm, 1)	11m 33s
e2e (ubuntu-latest, 22, esbuild, 0)	7m 51s
e2e (ubuntu-latest, 22, npm, 3)	8m 48s
e2e (ubuntu-latest, 22, esbuild, 3)	10m 45s
e2e (ubuntu-latest, 22, npm, 0)	11m 8s
e2e (ubuntu-latest, 22, npm, 5)	10m 28s
e2e-package-managers (ubuntu-latest-4core, 22, yarn, 0)	8m 42s
e2e (ubuntu-latest, 22, esbuild, 1)	9m 44s
e2e-package-managers (ubuntu-latest-4core, 22, yarn, 2)	7m 20s
e2e-package-managers (ubuntu-latest-4core, 22, pnpm, 1)	4m 43s
e2e-package-managers (ubuntu-latest-4core, 22, pnpm, 2)	5m 36s
e2e (ubuntu-latest, 22, esbuild, 4)	6m 58s
e2e (ubuntu-latest, 22, esbuild, 2)	9m 31s
e2e (ubuntu-latest, 22, npm, 2)	10m 58s
e2e (ubuntu-latest, 22, npm, 4)	8m 54s
e2e-package-managers (ubuntu-latest-4core, 22, pnpm, 0)	6m 32s
e2e-package-managers (ubuntu-latest-4core, 22, yarn, 1)	6m 2s
e2e (ubuntu-latest, 22, esbuild, 5)	7m 11s
e2e-snapshots	0s
e2e-windows-subset	4m 47s
	2h 48m 22s

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