Refs #35414 - Add sd_notify dependency to service

Puma has a soft dependency on sd_notify when systemd is used. In our
service we use this so we should make sure it's pulled in. Prior to
9b0652fed9f86fd429e237ce359422a1dba14a2a the dynflow_sidekiq group
pulled it in, which technically wasn't entirely correct but in practice
it worked. Sidekiq 6 has essentially vendored sd_notify so it was
removed.

Fixes: 9b0652fed9f86fd429e237ce359422a1dba14a2a