Nydus Image Service v2.1.1

Binaries download mirror (sync within a few hours): https://registry.npmmirror.com/binary.html?path=nydus/v2.1.1/

What's Changed

• action/nydus-test: stop on the first test failure by @changweige in #805
• Backport 3 patches for stable/v2.1 by @changweige in #828
• nydusify: drop label "nydus-blob-ids" from meta layer by @changweige in #830
• action: update release notes for download mirror by @imeoer in #834
• prepare for publishing to crates.io by @jiangliu in #838
• [backport to stable/v2.1] storage: add mirror health checking support by @imeoer in #839

Full Changelog: v2.1.0...v2.1.1