Do not give an error if both RAY_ADDRESS and address is specified on initialization (#13305)

* Finalize handling of RAY_ADDRESS

* lint

python/ray/worker.py

@@ -523,7 +523,7 @@ def init(
 
     You can also define an environment variable called `RAY_ADDRESS` in
     the same format as the `address` parameter to connect to an existing
-    cluster with ray.init().
+    cluster with ray.init() or ray.init(address="auto").
 
     Args:
         address (str): The address of the Ray cluster to connect to. If
@@ -532,7 +532,9 @@ def init(
             It will also kill these processes when Python exits. If the driver
             is running on a node in a Ray cluster, using `auto` as the value
             tells the driver to detect the the cluster, removing the need to
-            specify a specific node address.
+            specify a specific node address. If the environment variable
+            `RAY_ADDRESS` is defined and the address is None or "auto", Ray
+            will set `address` to `RAY_ADDRESS`.
         num_cpus (int): Number of CPUs the user wishes to assign to each
             raylet. By default, this is set based on virtual cores.
         num_gpus (int): Number of GPUs the user wishes to assign to each
@@ -634,13 +636,6 @@ def init(
     if "RAY_ADDRESS" in os.environ:
         if address is None or address == "auto":
             address = os.environ["RAY_ADDRESS"]
-        else:
-            raise RuntimeError(
-                "Cannot use both the RAY_ADDRESS environment variable and "
-                "the address argument of ray.init simultaneously. If you "
-                "use RAY_ADDRESS to connect to a specific Ray cluster, "
-                "please call ray.init() or ray.init(address=\"auto\") on the "
-                "driver.")
 
     # Convert hostnames to numerical IP address.
     if _node_ip_address is not None: