[Bugfix] - Changes in logic to delete share db

[TejasRGitHub]

Feature or Bugfix

• Bugfix

Detail

• Additional locking when revoking a dataset with the same database shared across various datasets
• Modifications in checks to see if the principal / database combo is still shared else where

Relates

Security

Please answer the questions below briefly where applicable, or write N/A. Based on
OWASP 10.

• Does this PR introduce or modify any input fields or queries - this includes
  fetching data from storage outside the application (e.g. a database, an S3 bucket)? N/A
  • Is the input sanitized?
  • What precautions are you taking before deserializing the data you consume? N/A
  • Is injection prevented by parametrizing queries?
  • Have you ensured no eval or similar functions are used?
• Does this PR introduce any functionality or component that requires authorization? N/A
  • How have you ensured it respects the existing AuthN/AuthZ mechanisms?
  • Are you logging failed auth attempts?
• Are you using or adding any cryptographic features? N/A
  • Do you use a standard proven implementations?
  • Are the used keys controlled by the customer? Where are they stored?
• Are you introducing any new policies/roles/users? N/A
  • Have you used the least-privilege principle? How?

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[TejasRGitHub]

Test cases:

Onboarded two dataset ( D1, D2 ) with the same common_db. Onboarded a consumption role ( C1 ). Environment has two roles ( Scientist, Engineers )

Scenerio 1:

1. Created a share S1 with table from C1 to D1 ✅ ( Checked if the tables are accessible via Athena )
2. Created a share S2 with table from C1 to D2 ✅ ( Checked if the tables are accessible via Athena )
3. Revoked share S2 and checked if the common_db_shared still exists in the account ✅
4. Queried tables from S1 to validate access and also checked if LF permissions for the principal exists ✅

Scenario 2:

1. Repeated steps 1 and 2.
2. Created another share S3 with D1 from environment role : Scientist
3. Checked if access to the table exists for this role ✅
4. Now revoked S1 and check if the access in S3 and S2 are intact ✅ ( Checked that the permission to the principals exists and Athena query works)
5. Revoked S3 and checked if the access to S2 is present ✅ ( Checked that the permission to the principals exists and Athena query works)
6. Revoked S2 and checked now that the shared database is deleted ✅

TODO
Scenario 3:

1. Repeat steps 1 and 2,
2. Onboard another dataset (D3) in another enviironment where the database name is the same i.e. common_db
3. Now make a share S1 from C1 to this dataset ( D3 ) and also make a share S2 with D2 or D1
4. Revoke share items in share S2 and check if the common_shared db is still present ✅