bpo-37105: Add deprecated-remove information on stream doc (#13672)

* Add deprecated-remove information on stream doc

According to the code on streams.py the functions:
``open_connection()``, ``start_server()``, ``open_unix_connection()``,
``start_unix_server()`` are deprecated. I infor that on
documentation.

Doc/library/asyncio-stream.rst

@@ -67,6 +67,10 @@ and work with streams:
 
       The *ssl_handshake_timeout* parameter.
 
+   .. deprecated-removed:: 3.8 3.10
+
+      `open_connection()` is deprecated in favor of `connect()`.
+
 .. coroutinefunction:: start_server(client_connected_cb, host=None, \
                           port=None, \*, loop=None, limit=None, \
                           family=socket.AF_UNSPEC, \
@@ -100,6 +104,10 @@ and work with streams:
 
       The *ssl_handshake_timeout* and *start_serving* parameters.
 
+   .. deprecated-removed:: 3.8 3.10
+
+      `start_server()` is deprecated if favor of `StreamServer()`
+
 
 .. rubric:: Unix Sockets
 
@@ -124,6 +132,10 @@ and work with streams:
 
       The *path* parameter can now be a :term:`path-like object`
 
+   .. deprecated-removed:: 3.8 3.10
+
+      `open_unix_connection()` is deprecated if favor of `connect_unix()`.
+
 
 .. coroutinefunction:: start_unix_server(client_connected_cb, path=None, \
                           \*, loop=None, limit=None, sock=None, \
@@ -146,6 +158,10 @@ and work with streams:
 
       The *path* parameter can now be a :term:`path-like object`.
 
+   .. deprecated-removed:: 3.8 3.10
+
+      `start_unix_server()` is deprecated in favor of `UnixStreamServer()`.
+
 
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