Fix duplicate wiki_name entries causing configuration issues

- Changed AylesburyValeCouncil wiki_name from 'Buckinghamshire' to 'Buckinghamshire (Aylesbury Vale)'
- Changed LondonBoroughEaling wiki_name from 'Ealing' to 'Ealing (London Borough)'
- Changed CumberlandAllerdaleCouncil wiki_name from 'Cumberland' to 'Cumberland (Allerdale)'

Fixes #1484: Resolves duplicate council listings in wiki and Home Assistant integration dropdown, and prevents mapping errors in config_flow.py

Author: drsp123isen