minor #15341 Fixed array notation for yaml file in session/database.rst (romantymoshyk)

This PR was submitted for the 5.x branch but it was merged into the 4.4 branch instead.

Discussion
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Fixed array notation for yaml file in session/database.rst

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Commits
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e4ddf56 Fixed array notation for yaml file in session/database.rst

Author: javiereguiluz

session/database.rst

@@ -92,7 +92,7 @@ and ``RedisProxy``:
                     # you can optionally pass an array of options. The only options are 'prefix' and 'ttl',
                     # which define the prefix to use for the keys to avoid collision on the Redis server 
                     # and the expiration time for any given entry (in seconds), defaults are 'sf_s' and null:
-                    # - { 'prefix' => 'my_prefix', 'ttl' => 600 }
+                    # - { 'prefix': 'my_prefix', 'ttl': 600 }
 
     .. code-block:: xml