Merge remote-tracking branch 'studip/5.0' into 5.0

app/controllers/calendar/calendar.php

app/controllers/oer/endpoints.php

app/controllers/profile.php

app/controllers/settings/details.php

app/views/calendar/single/_select_calendar.php

app/views/contents/overview/index.php

app/views/my_institutes/index.php

lib/classes/JsonApi/Routes/Courses/CoursesIndex.php

lib/classes/Seminar.class.php

lib/classes/sidebar/OptionsWidget.php

lib/extern/modules/views/persondetails_preview.inc.php

lib/models/Courseware/BlockTypes/Text.php

lib/models/User.class.php

lib/navigation/BrowseNavigation.php

public/export.php

.../plugins_packages/core/ContentsWidget/templates/index.php

public/sendfile.php

resources/assets/javascripts/bootstrap/forms.js

resources/assets/stylesheets/scss/contents.scss

resources/vue/components/courseware/CoursewareAudioBlock.vue