Store session value

Set a session value.

Available on :

Attribute	Type	Required	Description
type	string	✓	always `store_session_value_action`
key	string	✓	session key to set (1 <= length <= 100, must contain only letters, digits and underscores)
value	string	✓	value to store (1<=length<= 150)

{
    "type": "store_session_value_action",
    "key": "name",
    "value": "John Doe"
}