Remove unneeded imports

aleksis/apps/chronos/frontend/components/substitutions/SubstitutionCard.vue

 <script setup>
-import DeleteButton from "aleksis.core/components/generic/buttons/DeleteButton.vue";
 import SubstitutionInformation from "./SubstitutionInformation.vue";
-import LessonRelatedObjectChip from "../LessonRelatedObjectChip.vue";
 import TeacherField from "aleksis.apps.cursus/components/TeacherField.vue";
 import SubjectField from "aleksis.apps.cursus/components/SubjectField.vue";