Add test case to check that branches are correctly listed after CRUD operations

What does this MR do?

Add a test to attend the requirements of #48529 (closed).

What are the relevant issue numbers?

• #48529 (closed)
• https://gitlab.com/gitlab-org/quality/team-tasks/issues/84

Does this MR meet the acceptance criteria?

Note: I'll cover the acceptance criteria in a future iteration.

• [-] Changelog entry added, if necessary
• [-] Documentation created/updated
• Tests added for this feature/bug
• [-] Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• [-] Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
• [-] Security reports checked/validated by reviewer