Improve ci to generate better release body

[yrong]

Suggested Solution

• practice of moonbeam

https://github.com/PureStake/moonbeam/releases/tag/runtime-1400

maybe we can take moonbeam's [ci flow]((https://github.com/PureStake/moonbeam/blob/0eb967e9cb47e2b400c1011a7f9b77149b83054d/.github/workflows/release.yml#L229) as reference

release body generated in some script

[0x8f701]

same with: #943