Add support for reading the ruff version from Poetry groups (#127)

Not sure if this is a desired feature since this was requested already
(https://github.com/astral-sh/ruff-action/issues/40#issuecomment-2581207691)
without any sort of response.
Unfortunately Poetry doesn't yet support PEP 735
(https://github.com/python-poetry/poetry/issues/9751) and it doesn't
make sense to add ruff as a project dependency.

__tests__/fixtures/pyproject-dependency-poetry-project/pyproject.toml

@@ -0,0 +1,14 @@
+[project]
+name = "pyproject-dependency-poetry-project"
+version = "0.1.0"
+description = "Add your description here"
+readme = "README.md"
+requires-python = ">=3.12"
+
+[tool.poetry.group.dev.dependencies]
+sphinx = "*"
+ruff = "0.8.3"
+
+[build-system]
+requires = ["poetry-core>=2.0.0,<3.0.0"]
+build-backend = "poetry.core.masonry.api"

__tests__/fixtures/pyproject-dependency-poetry-project/src/pyproject_dependency_dev_project/__init__.py

@@ -0,0 +1,2 @@
+def hello() -> str:
+    return "Hello from python-project!"

__tests__/fixtures/pyproject-dependency-poetry-project/src/pyproject_dependency_dev_project/hello_world.py

@@ -0,0 +1 @@
+print("Hello world!")