fdo#74535: Write unit test for importing hyperlinks from xlsx.

Change-Id: I64e053106cee396a09f2a4915c19fcb1d69e5e82
fdo#74535: Don't forget clear the edit engine before re-using it.

Else you'd get a very comical result.

Change-Id: Ie73145dee47a8583f2e9cdb7ddb4f2d66f361dc1