v8.5: bump up the latest version to v8.5.6#22729

hfxsd wants to merge 1 commit intopingcap:feature/preview-v8.5.6pingcap/docs:feature/preview-v8.5.6from

hfxsd:bump-to-v8.8.6hfxsd/docs:bump-to-v8.8.6Copy head branch name to clipboard