Tidy up calls to post()

include/boost/beast/http/impl/read.ipp

@@ -170,10 +170,11 @@ operator()(
 
     upcall:
         if(! cont_)
-            return boost::asio::post(
-                s_.get_executor(),
-                bind_handler(std::move(h_),
-                    ec, bytes_transferred_));
+        {
+            BOOST_ASIO_CORO_YIELD
+            boost::asio::post(
+                bind_handler(std::move(*this), ec));
+        }
         h_(ec, bytes_transferred_);
     }
 }
@@ -290,7 +291,7 @@ operator()(
         if(Condition{}(p_))
         {
             BOOST_ASIO_CORO_YIELD
-            boost::asio::post(s_.get_executor(),
+            boost::asio::post(
                 bind_handler(std::move(*this), ec));
             goto upcall;
         }