chore(http2): collapse duplicate request stream setup (#5140)

Author: trivikr

lib/dispatcher/client-h2.js

@@ -866,26 +866,18 @@ function writeH2 (client, request) {
 
   // TODO(metcoder95): add support for sending trailers
   const shouldEndStream = body === null
+
   if (expectContinue) {
     headers[HTTP2_HEADER_EXPECT] = '100-continue'
-    stream = requestStream(headers, { endStream: shouldEndStream, signal })
-    if (stream == null) {
-      return false
-    }
-    stream[kHTTP2Stream] = true
-    bindRequestToStream(request, stream, null)
-  } else {
-    stream = requestStream(headers, {
-      endStream: shouldEndStream,
-      signal
-    })
-    if (stream == null) {
-      return false
-    }
-    stream[kHTTP2Stream] = true
-    bindRequestToStream(request, stream, null)
   }
 
+  stream = requestStream(headers, { endStream: shouldEndStream, signal })
+  if (stream == null) {
+    return false
+  }
+  stream[kHTTP2Stream] = true
+  bindRequestToStream(request, stream, null)
+
   // Increment counter as we have new streams open
   ++session[kOpenStreams]
   stream.setTimeout(requestTimeout)