Fix astro run command for Airflow 3 by using db migrate

[vinnyjth]

Fixes #2095

The astro run <dag-id> command fails on Airflow 3 runtime images because it was hardcoded to use airflow db init, which was removed in Airflow 3.0.

This commit adds version detection logic to the RunDAG function to conditionally use the appropriate database command:

• airflow db migrate for Airflow 3+
• airflow db init for Airflow 2

The fix follows the same pattern used in PR #1811 for the astro dev start command path.

Changes:

• Added call to checkAirflowVersion() in the RunDAG function
• Conditionally set dbCommand based on detected Airflow version
• Updated error messages to use the dynamic dbCommand variable
• Added test mocks for ListLabels() to support version detection
• Added new test case for Airflow 3 to verify the fix

Description

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🎟 Issue(s)

Related #XXX

🧪 Functional Testing

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📋 Checklist

• Rebased from the main (or release if patching) branch (before testing)
• Ran make test before taking out of draft
• Ran make lint before taking out of draft
• Added/updated applicable tests
• Tested against Astro-API (if necessary).
• Tested against Houston-API and Astronomer (if necessary).
• Communicated to/tagged owners of respective clients potentially impacted by these changes.
• Updated any related documentation