fix: page.pdf producing an invalid pdf

When defining a chunk size for <CDPSession>.send('IO.read', { handle, size }), the CDPSession will occassionally indicate an that it has reached the end of file without sending a full pdf. This is documented by the associated issue.

This behavior is not reproducable when leaving out the size parameter. Since the size parameter is not required on the CDPSession side and is merely a suggestion on the stream side, we can safely leave it out.

Refs: puppeteer#7757

src/common/helper.ts

@@ -356,12 +356,12 @@ async function getReadableFromProtocolStream(
 
   let eof = false;
   return new Readable({
-    async read(size: number) {
+    async read() {
       if (eof) {
         return null;
       }
 
-      const response = await client.send('IO.read', { handle, size });
+      const response = await client.send('IO.read', { handle });
       this.push(response.data, response.base64Encoded ? 'base64' : undefined);
       if (response.eof) {
         eof = true;