Change the warning message on project transfer to another namespace

What does this MR do?

Clarifies the warning message on project transfer to another namespace.

When a project owner transfer a project to another namespace, the project owner is the owner of the group/personal space, so they is NEVER "another owner" of the target group/personal space. As the transfer target is a namespace (group or personal space), this change would be reasonable.

Screenshots

before	after

Does this MR meet the acceptance criteria?

Conformity

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