Remove Vue 2 only entries from Components & Libraries

Remove 14 entries that only support Vue 2 with no Vue 3 migration.
Each repo was verified via GitHub API and README inspection to confirm
it does not support Vue 3.

Entries that appeared Vue 2 only based on their awesome-vue description
but have actually migrated to Vue 3 (e.g. v-tooltip, v-dialogs,
vue-draggable-resizable, vue-cropper) were kept.

Removed:
- element-ui (superseded by Element Plus)
- vux
- vue-element-admin (built on Element UI 2.x)
- D2 Admin
- Vitify Admin (Vue 2.7 + Vuetify 2)
- Vue-Access-Control
- vue-easytable
- Vue Pivottable
- vue-easy-toast
- vue2-leaflet
- Vue Datamaps
- vue-goodshare
- vue-signature
- vue-option-events

Relates to #4138, #4323