[Regression] env var DBT_TARGET violates the rule of specificity

[owenprough-sift]

Is this a new bug in dbt-core?

• I believe this is a new bug in dbt-core
• I have searched the existing issues, and I could not find an existing issue for this bug

Current Behavior

dbt improperly ignores the --target CLI flag when environment variable DBT_TARGET is set.

$ export DBT_TARGET=nonvalid_target
$ dbt build --project-dir /dbt --target dev
12:31:08  Running with dbt=1.8.3
12:31:08  Encountered an error:
Runtime Error
  The profile 'xxx' does not have a target named 'nonvalid_target'. The valid target names for this profile are: 
   - dev
   - prod

Expected Behavior

According to the documentation regarding flags (link):

The most specific setting "wins." If you set the same flag in all three places, the CLI option will take precedence, followed by the environment variable, and finally, the value in dbt_project.yml.

So I would expect the --target CLI option to be used even though the env var is set.

Steps To Reproduce

1. Set environment variable DBT_TARGET
2. Invoke dbt, passing the --target option for a target different than the contents of DBT_TARGET
3. Weep when dbt ignores --target and uses instead the contents of DBT_TARGET

Relevant log output

No response

Environment

- OS: Debian 11 (official python docker image `python:3.11-slim-bullseye`)
- Python: 3.11.9
- dbt: 1.8.3
- dbt-snowflake: 1.8.3

Which database adapter are you using with dbt?

snowflake

Additional Context

No response

[dbeatty10]

Thank you for raising this issue @owenprough-sift -- agreed that dbt should use the value of --target instead of DBT_TARGET 🎯

This looks like the issue reported in #10304.

What happens when you move --target to be before the build subcommand?

[owenprough-sift]

dbt --target dev build ... works as expected. But I'd still like #10304 to be fixed. 😉

[dbeatty10]

But I'd still like #10304 to be fixed. 😉

💯 ! We've got a fix in flight: #10423

In the meantime, I'm going to close this one as a special case of #10304

Thank you as always for your insights on what is/isn't working as it should 🙏