Nebula Graph是什么？

# # Copyright (c) 2020 vesoft inc. All rights reserved. # # This source code is licensed under Apache 2.0 License. header: license: spdx-id: Apache-2.0 copyright-owner: vesoft inc content: | Copyright (c) 2020 vesoft inc. All rights reserved. This source code is licensed under Apache 2.0 License. pattern: | Copyright (c) \d{4} vesoft inc. All rights reserved. This source code is licensed under Apache 2.0 License. paths-ignore: - '.licenserc.yaml' - '.clang-tidy' - '.dockerignore' - '**/.gitignore' - 'cmake' - 'conf' - 'docker' - 'package' - 'resources/*.csv' - 'resources/*.json' - 'scripts/*.service' - 'src/**/*.thrift' - 'src/**/*.lex' - 'src/**/*.yy' - 'src/**/*.dict' - 'src/**/*.in' - 'tests' - '.github' - '.linters' - '**/*.md' - 'third-party' - 'LICENSE' - 'NOTICE' comment: on-failure