[BUG] Breaking change detect tool doesn't detect breakings for a preview version

The https://github.com/Azure/azure-rest-api-specs/pull/33298 pr introduced a lot of un-approved api level breakings, but the breaking change detect tool didn't detect them. This [sdk pr](https://github.com/Azure/azure-sdk-for-js/pull/33989) is generate by above spec pr and most of the breakings in the sdk pr are from the spec breakings.

cc @MaryGao

Start by comparing the breaking-change detection results for spec PR 33298 with the generated SDK PR 33989, focusing on how preview versions are handled. Trace the detector entry point and reproduce the missed API-level breakings; done means unapproved breakings from the preview version are reported.

Written by the indexing model from the issue text.