implemented deleting collections

...ase_implementation/__pycache__/sqlite_api.cpython-312.pyc

database_implementation/sqlite_api.py

flask_backend.py

...tend/crisis-events-text-summarization-frontend/src/App.js

...events-text-summarization-frontend/src/collection_list.js

...s-events-text-summarization-frontend/src/database_util.js