Web Hook Test "Tag Push Event" sends the wrong "object_kind" and "ref" in the request body
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### Summary
We currently use Jenkins for managing our pipelines and we've setup the integrations in Gitlab. When testing the Tag Push Event, the sent _object_kind_ and _ref_ in the request body correspond to a Push Event test and not to a Tag Push Event. Specifically, the _object_kind_ contains "push" instead of "tag_push" and _ref_ points to the develop branch instead of the latest tag.
### Steps to reproduce
<!-- Describe how one can reproduce the issue - this is very important. Please use an ordered list. -->
1 - Create a project
2 - Submit some code and create a tag
3 - Configure an integration to an external tool (Jenkins)
4 - After the configuration of the integration, trigger a Tag Push Event test.

5 - Here is the current result:

6 - This is the expected result (obtained by doing a live tag push event:

### What is the current *bug* behavior?
<!-- Describe what actually happens. -->
As stated previously, the Tag Push Event test sends the incorrect _object_kind_ and _ref_ in the request body, simulating a Push Event instead of a Tag Push Event
### What is the expected *correct* behavior?
<!-- Describe what you should see instead. -->
We would like to see the Tag Push Event submitting an _object_kind_ of type "tag_push" instead of "push" and the _ref_ pointing to the latest tag in the project.
### Relevant logs and/or screenshots
Intended behaviour

Current behaviour

issue