Fix dicts.j2 template

[sysolyakin]

Hello!

I've tried to deploy the role with a list of dictionaries in clickhouse_dicts variable and got this error:

2021.08.17 14:32:32.316330 [ 15692 ] {} ExternalDictionariesLoader: Failed to load config file '/etc/clickhouse-server/auto_dictionary.xml': Poco::Exception. Code: 1000, e.code() = 0, e.displayText() = Exception: Failed to merge config with '/etc/clickhouse-server/conf.d/clickhouse_remote_servers.xml': Exception: Root element doesn't have the corresponding root element as the config file. It must be , Stack trace (when copying this message, always include the lines below):

According to documentation it must use tags <yandex></yandex> instead of <dictionaries>.

So, could you merge this PR, please?