Update doctrine.rst

* Added info about the slash in a "host" name like `/data/sockets/databases/postgresql` (took me hours to figure it out!)
* Added info that urlencoded parameters in conjunction with ``resolve:`` leads to an error message.

Author: ThomasLandauer

doctrine.rst

@@ -49,10 +49,12 @@ The database connection information is stored as an environment variable called
 
 .. caution::
 
-    If the username, password or database name contain any character considered
-    special in a URI (such as ``!``, ``@``, ``$``, ``#``), you must encode them.
+    If the username, password, host or database name contain any character considered
+    special in a URI (such as ``!``, ``@``, ``$``, ``#``, ``/``), you must encode them.
     See `RFC 3986`_ for the full list of reserved characters or use the
-    :phpfunction:`urlencode` function to encode them.
+    :phpfunction:`urlencode` function to encode them. In this case you need to remove
+    the ``resolve:`` prefix in ``config/packages/doctrine.yaml``:
+    ``url: '%env(resolve:DATABASE_URL)%'``
 
 Now that your connection parameters are setup, Doctrine can create the ``db_name``
 database for you: