Sort exported names

Signed-off-by: Sahas Subramanian <[email protected]>

Author: shsms

src/frequenz/channels/experimental/__init__.py

@@ -17,7 +17,7 @@
 
 __all__ = [
     "OptionalReceiver",
-    "WithPrevious",
     "Pipe",
     "RelaySender",
+    "WithPrevious",
 ]