Notify systemd on sentinel startup (#7168)
Notify systemd on sentinel startup (#7168)

Co-authored-by: Daniel Murnane <7f882bc785e747c3022c069fa56d236771cecc54@eitccorp.com>
JackieXie168/redis,JackieXie168/redis,JackieXie168/redis,JackieXie168/redis