Bump pytest-asyncio from 1.3.0 to 1.4.0 (#307)

Author: frequenz-auto-dependabot[bot]

pyproject.toml

@@ -102,7 +102,7 @@ dev-pytest = [
   "pytest == 9.0.3",
   "frequenz-repo-config[extra-lint-examples] == 0.17.0",
   "pytest-mock == 3.15.1",
-  "pytest-asyncio == 1.3.0",
+  "pytest-asyncio == 1.4.0",
   "async-solipsism == 0.9",
   "time-machine == 3.2.0",
   "hypothesis == 6.155.1",