v0.4.2-nightly

What's Changed

Build/Testing/CI

• Replace github label action with FuseBot (#590) by @bohutang

Dependency Updates

• Bump metrics from 0.15.1 to 0.16.0 (#583) by @dependabot[bot]
• Bump metrics-exporter-prometheus from 0.4.0 to 0.5.0 (#584) by @dependabot[bot]
• Bump vergen from 5.1.5 to 5.1.6 (#570) by @dependabot[bot]
• Bump tokio-stream from 0.1.5 to 0.1.6 (#555) by @dependabot[bot]
• Bump futures from 0.3.14 to 0.3.15 (#554) by @dependabot[bot]
• Bump serde from 1.0.125 to 1.0.126 (#556) by @dependabot[bot]
• Bump tokio from 1.5.0 to 1.6.0 (#553) by @dependabot[bot]

Others

• fix typo ErrorCodes::SyntexException (#589) by @b41sh
• [common/exception] make life easier by rewriting error conversion with trait From (#580) by @drmingdrmer
• Allow PlanNode to have multiple children (#563) by @leiysky
• Bump metrics from 0.15.1 to 0.16.0 (#583) by @dependabot[bot]
• Bump metrics-exporter-prometheus from 0.4.0 to 0.5.0 (#584) by @dependabot[bot]
• Bump rust-toolchain to nightly-2021-05-06 (#576) by @bohutang
• Add SUBSTRING function to doc (#572) by @bohutang
• Bump vergen from 5.1.5 to 5.1.6 (#570) by @dependabot[bot]
• Refactor scripts structure (#571) by @bohutang
• Datasource API (#562) by @bohutang
• [store] test: use global mono-incr seq to generate port, to avoid port conflict during the concurrent test (#566) by @drmingdrmer
• Parquet appender (#565) by @dantengsky
• optimizer: refactor optimizer (#561) by @bohutang
• Fix Aggregate Check bug (#542) by @jyizheng
• Bump tokio from 1.5.0 to 1.6.0 (#553) by @dependabot[bot]
• Support system.contributors table (#549) by @bohutang
• [store] support restarting a MetaNode. (#551) by @drmingdrmer
• Add performance bench gif (#547) by @bohutang
• [exception] better exception (#545) by @sundy-li
• Change to github icon for website (#544) by @bohutang
• Add notes for docs example (#539) by @bohutang
• Fix deploy action and replace favicon (#534) by @bohutang
• Change the docs website to mkdocs-material (#529) by @bohutang
• [store] meta: support remote write; refactor boot() (#528) by @drmingdrmer
• Update FuseQuery v0.4.1 vs ClickHouse 21.4.6 performance comparsion (#527) by @bohutang