Create an exportable util for markdownlint

[junhaoliao]

Request

A markdownlint config exists at exports/lint-configs/.markdownlint-cli2.yaml but currently there is no linting go-task provided. developers who wish to apply this lint config on markdown docs need to look up the command to run with this config

https://github.com/y-scope/yscope-dev-utils/blob/2693d8b69050b8d48f96ae60cfce7be8626d3875/exports/lint-configs/.markdownlint-cli2.yaml

Possible implementation

refer to https://github.com/y-scope/clp/blob/main/taskfiles/lint.yaml to provide a check and a fix variant