kiri improvements

- pull newest image directly from [https://github.com/leoheck/kiri-docker](https://github.com/leoheck/kiri-docker) instead of making our own
- it'll be better updated in the future?
- at least there are probably more differences from the newest kiri-docker and usa-reddragon's but with 9.0 instead of 7.0
- automatically delete older comments since they're all pointing to the same link and clutters the comments
- referring to this: `Kiri diff output is available at https://hacker-fab.github.io/phoenix/pr-previews/28/web/index.html`
- kinda like pinning it to the bottom (since that's where you usually look)
- making the deployment faster since it takes a couple minutes
- fix the "create release" error so `kiri-github-action` isn't red
- the github action [`create-release`](https://github.com/actions/create-release) is deprecated
- why??
- fix the automatic issue maker thing (or just deleting it) so it isn't red
- has to do with "assignees" is outdated?