doc: fix stream iterator helpers examples

Our examples don't run because of a typo and when I asked for feedback on something unrelated I got told that :)

Trying to create a PR from the GitHub UI since I am OOO for a bit. I haven't done a PR from GH in a while so hopefully it's not too much trouble

cc @MoLow @ronag @nodejs/streams

doc/api/stream.md

@@ -2239,7 +2239,7 @@ const anyBigFile = await Readable.from([
   'file3',
 ]).some(async (fileName) => {
   const stats = await stat(fileName);
-  return stat.size > 1024 * 1024;
+  return stats.size > 1024 * 1024;
 }, { concurrency: 2 });
 console.log(anyBigFile); // `true` if any file in the list is bigger than 1MB
 console.log('done'); // Stream has finished
@@ -2291,7 +2291,7 @@ const foundBigFile = await Readable.from([
   'file3',
 ]).find(async (fileName) => {
   const stats = await stat(fileName);
-  return stat.size > 1024 * 1024;
+  return stats.size > 1024 * 1024;
 }, { concurrency: 2 });
 console.log(foundBigFile); // File name of large file, if any file in the list is bigger than 1MB
 console.log('done'); // Stream has finished
@@ -2341,7 +2341,7 @@ const allBigFiles = await Readable.from([
   'file3',
 ]).every(async (fileName) => {
   const stats = await stat(fileName);
-  return stat.size > 1024 * 1024;
+  return stats.size > 1024 * 1024;
 }, { concurrency: 2 });
 // `true` if all files in the list are bigger than 1MiB
 console.log(allBigFiles);