Bump attrs from 24.2.0 to 25.3.0

Bumps [attrs](https://github.com/sponsors/hynek) from 24.2.0 to 25.3.0.
- [Commits](https://github.com/sponsors/hynek/commits)

---
updated-dependencies:
- dependency-name: attrs
  dependency-version: 25.3.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

src/backend/requirements.txt

@@ -21,7 +21,7 @@ async-timeout==5.0.1
     #   asyncpg
 asyncpg==0.30.0
     # via fastapi-app (pyproject.toml)
-attrs==24.2.0
+attrs==25.3.0
     # via aiohttp
 azure-core==1.32.0
     # via