Fix Power BI trigger testcase

[ambika-garg]

---

^ Add meaningful description above
Read the Pull Request Guidelines for more information.
In case of fundamental code changes, an Airflow Improvement Proposal (AIP) is needed.
In case of a new dependency, check compliance with the ASF 3rd Party License Policy.
In case of backwards incompatible changes please leave a note in a newsfragment file, named {pr_number}.significant.rst or {issue_number}.significant.rst, in newsfragments.

[ambika-garg]

Hey @eladkal and @dabla, This pull request fixes the test case of powerbi_trigger, that initially took 30 seconds to execute. It is in continuation to PR #41331.

[potiuk]

Looks like mypy does not like it :)

[dabla]

Thank you @ambika-garg for the fix