[CT-3238] Display the metric definition/configuration in dbt docs

[siljamardla]

Describe the feature

Related to #466
I would expect to be able to see the metric configuration so that I could understand how this is set up.
Just like we see the dbt model code in dbt docs.

Describe alternatives you've considered

Manually copy-pasting the configurations into the description section.
Automatically extracting the configurations from YAML files and pasting the definition into the descriptions.
Neither are actual solutions, they are both very bad workarounds for lacking functionality in dbt docs.

Additional context

Who will this benefit?

Anyone who needs to understand how the metric has been set up (what is the definition of the metric).
It is also beneficial to show the configs to users who are less involved in setting up the metrics. They will eventually get used to the syntax and will be able to contribute into metric setup.

Are you interested in contributing this feature?

Sure

[github-actions]

This issue has been marked as Stale because it has been open for 180 days with no activity. If you would like the issue to remain open, please comment on the issue or else it will be closed in 7 days.

[github-actions]

Although we are closing this issue as stale, it's not gone forever. Issues can be reopened if there is renewed community interest. Just add a comment to notify the maintainers.