Drop custom _error_tag and use error_tag provided by dbt-common

[QMalcolm]

Housekeeping

• I am a maintainer of dbt-core

Short description

In #9886 we added a stop gap _error_tag to core which really should belong in dbt-common. Closing dbt-labs/dbt-common#107 will mean it exists in dbt-common. Once dbt-common releases that feature, we should migrate to using that and drop the custom implementation in core.

Acceptance criteria

• _error_tag implementation in core is delete
• things using core's _error_tag use dbt-common's error_tag

Suggested Tests

N/A

Impact to Other Teams

N/A

Will backports be required?

N/A

Context

No response