{CI} Fix policy migration issue

[wangzelin007]

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There is a breaking change happening during the automated migration.
The action: Opened condition is added by this PR during the automated migration, so policy will not act when someone add labels.
Possible solution: use action: Labeled.

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• Have you run azdev style <YOUR_EXT> locally? (pip install azdev required)
• Have you run python scripts/ci/test_index.py -q locally?

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• My extension description/summary conforms to the Extension Summary Guidelines.

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[azure-client-tools-bot-prd]

️✔️Azure CLI Extensions Breaking Change Test

️✔️Non Breaking Changes

[azure-client-tools-bot-prd]

Hi @wangzelin007,
Please write the description of changes which can be perceived by customers into HISTORY.rst.
If you want to release a new extension version, please update the version in setup.py as well.

[yonzhan]

CI