Remove `hydrogen_container_image_registry_prefix_*`

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

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

@@ -20,8 +20,6 @@ hydrogen_container_image_self_build_repo: "https://github.com/element-hq/hydroge
 # renovate: datasource=docker depName=ghcr.io/element-hq/hydrogen-web
 hydrogen_version: v0.5.1
 hydrogen_container_image: "{{ hydrogen_container_image_registry_prefix }}element-hq/hydrogen-web:{{ hydrogen_version }}"
-hydrogen_container_image_registry_prefix: "{{ 'localhost/' if hydrogen_container_image_self_build else hydrogen_container_image_registry_prefix_upstream }}"
-hydrogen_container_image_registry_prefix_upstream: "{{ hydrogen_container_image_registry_prefix_upstream_default }}"
 hydrogen_container_image_registry_prefix_upstream_default: ghcr.io/
 hydrogen_container_image_force_pull: "{{ hydrogen_container_image.endswith(':latest') }}"