Importing TestNG Execution results via API is duplicating tests

Description
When importing TestNG results via the standard endpoint (/api/v1/import/execution/testng), if we encounter a Generic test with an identical definition to the test provided in the XML, we're not currently performing a verification. This results in the creation of a new test instead.

Pre-conditions

• Have an API Key setup;
• Have a TestNG XML Results file

How to reproduce
1) Send a POST request to the TestNG endpoint with the XML file in the body 

https://xray.cloud.getxray.app/api/v1/import/execution/testng?testExecKey=XNP-23

2) Send the same POST request with the same XML file

Actual result/Attachments

The first request will create a Test based on the XML definition, along with a new test execution, and subsequently link the created test to it.
The second request will produce another new Test, also with the same definition, along with a new test execution, and link the newly created Test to it.

Expected result

The first request creates a new Test with the provided definition and includes it in the Execution. Subsequently, the second request generates a new Execution and should include the Test created in the first request instead of creating a new Test.