More CI cleanup, add style workflow (#107)

- Changes on the `test.yml` workflow:
  - Using poetry instead of pip. Contrary to what I wrote in #75, it is possible to use poetry (and have the benefits of shorter install times) without the need for having two separate versions of `pyproject.toml` and `poetry.lock`.
  - Reduce the trigger scope to only run when files in these directories are modified:
    - `lerobot/`
    - `tests/`
    - `examples/`
    - `.github/`
- Add `style.yml` workflow for doing a `ruff check` pass on the code
- More cleanup (removed deprecated workflow)

.github/workflows/test.yml

@@ -4,9 +4,19 @@ on:
   pull_request:
     branches:
       - main
+    paths:
+      - "lerobot/**"
+      - "tests/**"
+      - "examples/**"
+      - ".github/**"
   push:
     branches:
       - main
+    paths:
+      - "lerobot/**"
+      - "tests/**"
+      - "examples/**"
+      - ".github/**"
 
 jobs:
   tests:
@@ -21,26 +31,27 @@ jobs:
           ssh-private-key: ${{ secrets.SSH_PRIVATE_KEY }}
 
       - uses: actions/checkout@v4
-        with:
-          lfs: true
+
+      - name: Install EGL
+        run: sudo apt-get update && sudo apt-get install -y libegl1-mesa-dev
+
+      - name: Install poetry
+        run: |
+          pipx install poetry && poetry config virtualenvs.in-project true
+          echo "${{ github.workspace }}/.venv/bin" >> $GITHUB_PATH
 
       - name: Set up Python 3.10
         uses: actions/setup-python@v5
         with:
           python-version: "3.10"
-          cache: ${{ (github.ref == 'refs/heads/main') && 'pip' || '' }}
-          cache-dependency-path: pyproject.toml
+          cache: "poetry"
 
-      - name: Install EGL
-        run: sudo apt-get update && sudo apt-get install -y libegl1-mesa-dev
-
-      - name: Install pip dependencies
+      - name: Install poetry dependencies
         run: |
-          python -m pip install --upgrade pip
-          pip install -e ".[test, aloha, xarm, pusht]"
+          poetry install --all-extras
 
       - name: Test with pytest
-        run: pytest -v --cov=./lerobot tests
+        run: pytest -v --cov=./lerobot --durations=0 tests
 
       - name: Test end-to-end
         run: make test-end-to-end