### What changes were proposed in this pull request?
This PR adds a release announce template.
### Why are the changes needed?
- We want to use a formal template including HTTPS in the future release.
- The future release managers don't need to search mailing list to find this form.
### Does this PR introduce any user-facing change?
No.
### How was this patch tested?
N/A.
Closes#25656 from dongjoon-hyun/SPARK-28951.
Authored-by: Dongjoon Hyun <dhyun@apple.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
