Add flush parameter to captured_request()

It had just been forgotten.

Signed-off-by: David Plowman <[email protected]>

examples/request_context_manager.py

@@ -8,6 +8,8 @@
 with Picamera2() as picam2:
     picam2.start()
 
-    for _ in range(50):
+    for _ in range(25):
         with picam2.captured_request() as request:
             print(request)
+        with picam2.captured_request(flush=True) as request:
+            print(request)

picamera2/picamera2.py

@@ -1478,9 +1478,9 @@ def capture_request_and_stop_(self):
         return self.dispatch_functions(functions, wait, signal_function, immediate=True)
 
     @contextlib.contextmanager
-    def captured_request(self):
+    def captured_request(self, flush=None):
         """Capture a completed request using the context manager which guarantees its release."""
-        request = self.capture_request()
+        request = self.capture_request(flush=flush)
         try:
             yield request
         finally: