fix(ShareEntryLinkedList): Correctly propagate share data

`this.shares.unshift` mutates the share object for every component that uses
the share mixin.

Using the immutable approach changes the array reference which makes the mixin
lose track of the share object.

It would have been better to bubble up the share object but here we are :)

Signed-off-by: fenn-cs <[email protected]>

apps/files_sharing/src/views/SharingLinkList.vue

@@ -118,7 +118,7 @@ export default {
 		 */
 		addShare(share, resolve) {
 			// eslint-disable-next-line vue/no-mutating-props
-			this.shares = [share, ...this.shares]
+			this.shares.unshift(share)
 			this.awaitForShare(share, resolve)
 		},