Bump ruamel-yaml from 0.18.6 to 0.18.9 in /src

Bumps ruamel-yaml from 0.18.6 to 0.18.9.

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

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

src/requirements.txt

@@ -26,7 +26,7 @@ idna==3.10
     # via
     #   anyio
     #   httpx
-ruamel-yaml==0.18.6
+ruamel-yaml==0.18.9
     # via -r requirements.in
 ruamel-yaml-clib==0.2.12
     # via ruamel-yaml