Used polyfill instead of shim for collectStream

The full verification will come in the final streaming PR, so lets use pollyfil now

src/packages/emmett/src/streaming/collect.ts

@@ -1,4 +1,4 @@
-import type { ReadableStream } from '../shims/streams';
+import type { ReadableStream } from 'web-streams-polyfill';
 
 export const collectStream = async <T>(
   reader: ReadableStream<T>,