Unskip tests for Spherical Quantizer Type

https://github.com/Azure/azure-sdk-for-python/pull/44502 added tests for Spherical Quantizer Type for vector indexes in indexing policy. Currently the feature unavailable in prodduction yet, but the tests were manually ran in stage environment, and passed all tests.

Once the feature is available in production, these tests must be unskipped by removing `@unittest.skip` in tests