Artifact-modal LinkField e2e test fails because the suggested default link type is reset to "is Child of".

During the migration Hybrids: 8.2.2 -> 9.0.0, we had to refactor a bit the LinkField custom element because of the breaking changes introduced in the major version.

In planning-v2, there is a business rule saying: Given an artifact, When It has no parent artifact, Then the link type suggested by default should be "is Child of".

Before the migration, in a planning-v2 context, the behavior was:

- Given a link selected with the type "is Child of", When the link type changes, Then the link type suggested by default is "is Linked to"

After the migration, still in a planning-v2 context, the behavior is:

- Given a link selected with the type "is Child of", When the link type changes, Then the link type suggested by default is set back to "is Child of".

This new behavior seems more legit than the previous one. Let's keep it and update the Cypress test instead.