Fix url key of createFileOutput options for streaming #638

Job	Run time
test (node, 20.x)	27s
build (20.x)	12s
test (node, 18.x)	30s
test (node, 22.x)	24s
integration-browser (browser, webkit, 20.x)	54s
integration-deno (deno, v1.x)	7s
integration-browser (browser, firefox, 20.x)	50s
integration-browser (browser, chromium, 20.x)	49s
integration-edge (cloudflare-worker, 20.x)	18s
integration-node (esm, 18.x)	12s
integration-bun (bun, 1.0.11)	8s
integration-node (commonjs, 18.x)	10s
integration-node (commonjs, 20.x)	15s
integration-nextjs (nextjs, 20.x)	28s
integration-node (typescript, 18.x)	14s
integration-node (esm, 20.x)	10s
integration-node (typescript, 20.x)	12s
	6m 20s

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