Bugfix: Resolve incorrect truncation of long display names in Manage Accounts

Resolved the bug where long display names were truncated incorrectly in the Manage Accounts view.
Now, display names are properly truncated in the middle with ellipsis (...) to maintain readability.

https://github.com/owncloud/android/issues/4351
https://github.com/owncloud/android/pull/4380
