small resume/suspend fix

Author: tanner0101

Sources/TCP/Streams/TCPSocketSink.swift

@@ -56,7 +56,11 @@ public final class TCPSocketSink: Async.InputStream {
                 fatalError("SocketSink upstream is illegally overproducing input buffers.")
             }
             inputBuffer = input
-            writeData(ready: ready)
+            guard currentReadyPromise == nil else {
+                fatalError("SocketSink currentReadyPromise illegally not nil during input.")
+            }
+            currentReadyPromise = ready
+            resumeIfSuspended()
         case .close:
             close()
         case .error(let e):

Sources/TCP/Streams/TCPSocketSource.swift

@@ -60,7 +60,7 @@ public final class TCPSocketSource: Async.OutputStream {
     /// See OutputStream.output
     public func output<S>(to inputStream: S) where S: Async.InputStream, S.Input == Output {
         downstream = AnyInputStream(inputStream)
-        readData()
+        resumeIfSuspended()
     }
 
     /// Cancels reading