refactor(changelog): update changelog generation process and format#1528

Ipriyankrajai wants to merge 5 commits into

superset-sh:mainsuperset-sh/superset:mainfrom

Ipriyankrajai:pri/ss-7-change-log-on-releaseIpriyankrajai/superset:pri/ss-7-change-log-on-releaseCopy head branch name to clipboard