use GeneratedRegex property

[WeihanLi]

Use GeneratedRegex as property

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Use GeneratedRegex as property for better readibility

[dotnet-policy-service]

Thanks for your PR, @WeihanLi. Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[WeihanLi]

The failed test case seemed not related, could we try to re-run the failed ci

[dotnet-policy-service]

Looks like this PR hasn't been active for some time and the codebase could have been changed in the meantime.
To make sure no conflicting changes have occurred, please rerun validation before merging. You can do this by leaving an /azp run comment here (requires commit rights), or by simply closing and reopening.