Legal cron job community

Added integration test for legal CRON job to verify the issue and related fix.

The test requires two partitions and environment variables for the second storage account (AZURE_LEGAL_STORAGE_ACCOUNT_SECOND) and second data-partition id ( MY_SECOND_TENANT) in pipeline.

If these variables are not present then test will be skipped.

Legal service has limitation that it does not offer APIs to manage lifecycle of Legal_COO.json file. As we want to validate existing issue, limitations are captured by this issue: #110.