Fix bug in Bulk Delete E2E tests

Type of change

• Bug Fix
• Feature
• Pipeline
• Test
• Documentation

Does this introduce a change in the core logic?

• No
• Yes

Does this introduce a change in the cloud provider implementation, if so which cloud?

• AWS
• Anthos
• Azure
• GCP
• IBM

Does this follow conventional commits spec?

• No
• Yes

Have you set the target Milestone?

• No
• Yes

Have you set the no-detached-pipeline label?

• No
• Yes

Updates description?

We noticed a bug that blobs weren't properly uploaded into Azure Storage in bulk delete E2E test suite. The reason was that the generated sas token didn't contain the virtual folder of the blob. This MR contains a fix for it and adds 2 new steps checking that the blob is in Azure Storage by downloading the blob using the generated SAS token.

Additionally, the MR contains small refactoring of the Bulk delete suite.