Fix "Invalid JSON configuration, must be a dict"

[microhuang]

Wrong variable name used

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[boring-cyborg]

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[uranusjr]

For other reviewers: conf is a global variable made available by from airflow import conf. The trigger view does not contain a conf local variable, only request_conf = request.values.get("conf"), default_conf (either request_conf or json.dumps(dag.params)), and run_conf populated here.

[kaxil]

Thanks @microhuang

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!