build(deps): bump peewee from 3.17.6 to 3.17.8 in /backend

Bumps [peewee](https://github.com/coleifer/peewee) from 3.17.6 to 3.17.8.
- [Release notes](https://github.com/coleifer/peewee/releases)
- [Changelog](https://github.com/coleifer/peewee/blob/master/CHANGELOG.md)
- [Commits](https://github.com/coleifer/peewee/compare/3.17.6...3.17.8)

---
updated-dependencies:
- dependency-name: peewee
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

backend/requirements.txt

@@ -18,7 +18,7 @@ aiofiles
 
 sqlalchemy==2.0.32
 alembic==1.14.0
-peewee==3.17.6
+peewee==3.17.8
 peewee-migrate==1.12.2
 psycopg2-binary==2.9.9
 pgvector==0.3.5