Move `hydrogen_hostname` to `matrix_servers`

Signed-off-by: Suguru Hirahara <did🔑z6MkvVZk1A3KBApWJXv2Ju4H14ErDfRGxh8zxdXSZ4vACDg5>

group_vars/matrix_servers

@@ -4159,6 +4159,8 @@ hydrogen_self_check_validate_certificates: "{{ matrix_playbook_ssl_enabled }}"
 
 hydrogen_base_path: "{{ matrix_base_data_path }}/client-hydrogen"
 
+hydrogen_hostname: "{{ matrix_server_fqn_hydrogen }}"
+
 ######################################################################
 #
 # /hydrogen

roles/custom/matrix-client-hydrogen/defaults/main.yml

@@ -137,9 +137,6 @@ hydrogen_hsts_preload_enabled: false
 
 hydrogen_scheme: https
 
-# The hostname at which Hydrogen is served.
-hydrogen_hostname: "{{ matrix_server_fqn_hydrogen }}"
-
 # The path at which Hydrogen is exposed.
 # This value must either be `/` or not end with a slash (e.g. `/hydrogen`).
 hydrogen_path_prefix: /