🏡 Add `neighborhood` column to `locations` table, ensure migrations work with make commands

[FedericoDM]

Describe your changes

• Adjusted env.py file to push app context for migrations.
• Added migration docs to README
• Fixed directory in alembic file to run migrations from Makefile
• Add neighborhood column to locations table in database..py
• Run migration (new .py shows in versions folder)

Non-obvious technical information

• Migrations can be run with Makefile commands now (see README)
• The migration includes some other changes (changing some columns to nullable) that had been made before, but hadn't been included in the migration.

Checklist before requesting a review

• [x] pre-commit run --all-files (run before pushing)
• [x] pytest if applicable
• [x] Link issue
• [x] Update relevant documentation if applicable: doc strings, readme, poetry.

HERE IS SOME COMMAND LINE OUTPUT

(new-arrivals-chi-py3.11) root@LAPTOP-RMMEN33V:/mnt/c/Users/fdmol/Desktop/MSCAPP/new-arrivals-chi# make create_revision
alembic --config=./new_arrivals_chi/migrations/alembic.ini revision --autogenerate
INFO  [alembic.runtime.migration] Context impl PostgresqlImpl.
INFO  [alembic.runtime.migration] Will assume transactional DDL.
/mnt/c/Users/fdmol/Desktop/MSCAPP/new-arrivals-chi/new_arrivals_chi/migrations/env.py:120: SAWarning: Cannot correctly sort tables; there are unresolvable cycles between tables "hours, locations, organizations, users", which is usually caused by mutually dependent foreign key constraints.  Foreign key constraints involving these tables will not be considered; this warning may raise an error in a future release.
  context.run_migrations()
INFO  [alembic.ddl.postgresql] Detected sequence named 'services_id_seq' as owned by integer column 'services(id)', assuming SERIAL and omitting
INFO  [alembic.ddl.postgresql] Detected sequence named 'service_dates_id_seq' as owned by integer column 'service_dates(id)', assuming SERIAL and omitting
INFO  [alembic.ddl.postgresql] Detected sequence named 'languages_id_seq' as owned by integer column 'languages(id)', assuming SERIAL and omitting
INFO  [alembic.autogenerate.compare] Detected NULL on column 'hours.created_by'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'languages.created_by'
INFO  [alembic.autogenerate.compare] Detected added column 'locations.neighborhood'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'locations.created_by'
INFO  [alembic.autogenerate.compare] Detected type change from VARCHAR(length=255) to String(length=260) on 'organizations.name'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'organizations.location_id'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'organizations.hours_id'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'organizations.created_by'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'service_dates.created_by'
INFO  [alembic.autogenerate.compare] Detected NULL on column 'services.created_by'
  Generating /mnt/c/Users/fdmol/Desktop/MSCAPP/new-arrivals-chi/new_arrivals_chi/migrations/versions/2024-05-15-2010_feba3a15cf10_.py ...  done