make hookshot honor the matrix_bridges_encryption_enabled var

roles/custom/matrix-bridge-hookshot/defaults/main.yml

@@ -74,7 +74,7 @@ matrix_hookshot_cache_redisUri: "{{ ('redis://' + matrix_hookshot_cache_redis_ho
 # - support to also be enabled in the homeserver, see the documentation of Hookshot.
 # - Hookshot to be pointed at a Redis instance via the `matrix_hookshot_cache_redis*` variables.
 # See: https://matrix-org.github.io/matrix-hookshot/latest/advanced/encryption.html
-matrix_hookshot_encryption_enabled: false
+matrix_hookshot_encryption_enabled: "{{ matrix_bridges_encryption_enabled }}"
 
 # Controls whether metrics are enabled in the bridge configuration.
 # Enabling them is usually enough for a local (in-container) Prometheus to consume them.