Delete metrics package, update dbt_artifacts version

[SamHarting]

Description & motivation

There is an error on the main branch related to the metrics package and the dbt_artifacts package. Since we don't use the metrics package anymore I deleted that and the related models. The dbt_artifacts package I just updated to the latest version.

Changes to existing models:

Deleted a finance metric and an aggregation metric.

Screenshots (DAG, query results):

n/a

Validation of models:

n/a

Checklist:

• My pull request represents one logical piece of work.
• My commits are related to the pull request and look clean.
• My SQL follows the dbt Labs style guide.
• I have materialized my models appropriately.
• I have added appropriate tests and documentation to any new models or fields.
• I have noted if my changes break something in Looker and have a corresponding Looker PR to resolve the breaking change