dashboard subcommand for Mackerel dashboard management

[mashiike]

motivation

I want to write the definition of SLO in Markdown when creating an SLI / SLO dashboard. Since shimesaba also manages SLO, it will be managed in 2nd place, which is a problem. Therefore, I think it would be nice if shimesaba could manage the SLI / SLO dashboard.

Implementation plan

make dashboard subcommand.
The current behavior is the run subcommand.

The run command is implicitly executed when the Lambda function is running.

• shimesaba dashboard pull: Get json of dashboard definition from url written in config
• shimesaba dashboard push: Create or update dashboard

API Docs

https://mackerel.io/ja/api-docs/entry/dashboards#create