6.20.6

What's Changed

Internal changes

• CI: Make the perf PR comment and table more readable by @alies-dev in #12922
• Add guzzle/promises to the perf corpus by @alies-dev in #12984
• Push the docker image to ghcr.io/psalm/psalm by @danog in #13044

Full Changelog: 6.20.5...6.20.6