What's Changed
* docs: tidy design decisions section, including adding contents by michalc in https://github.com/uktrade/pg-sync-roles/pull/148
* docs: fix design decisions toc by michalc in https://github.com/uktrade/pg-sync-roles/pull/149
* docs: fix typo by michalc in https://github.com/uktrade/pg-sync-roles/pull/150
* fix: login behaviours when valid_until is None and no password by michalc in https://github.com/uktrade/pg-sync-roles/pull/151
**Full Changelog**: https://github.com/uktrade/pg-sync-roles/compare/v0.0.47...v0.0.48