Bump async-solipsism from 0.8 to 0.9

Bumps [async-solipsism](https://github.com/bmerry/async-solipsism) from 0.8 to 0.9.
- [Commits](bmerry/async-solipsism@0.8...0.9)

---
updated-dependencies:
- dependency-name: async-solipsism
  dependency-version: '0.9'
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pyproject.toml

@@ -102,7 +102,7 @@ dev-pytest = [
   "frequenz-repo-config[extra-lint-examples] == 0.13.8",
   "pytest-mock == 3.15.1",
   "pytest-asyncio == 1.3.0",
-  "async-solipsism == 0.8",
+  "async-solipsism == 0.9",
   "time-machine == 3.2.0",
   "hypothesis == 6.151.4",
   "frequenz-client-dispatch[cli]",