ci: properly install sqlalchemy2 deps; avoid relocking as a dependency

.github/workflows/ibis-backends.yml

@@ -585,51 +585,9 @@ jobs:
         with:
           flags: backend,pyspark,${{ runner.os }},python-${{ steps.install_python.outputs.python-version }}
 
-  gen_lockfile_sqlalchemy2:
-    name: Generate Poetry Lockfile for SQLAlchemy 2
-    runs-on: ubuntu-latest
-    steps:
-      - name: checkout
-        uses: actions/checkout@v4
-
-      - name: install python
-        uses: actions/setup-python@v5
-        with:
-          python-version: "3.11"
-
-      - run: python -m pip install --upgrade pip 'poetry==1.7.1'
-
-      - name: remove deps that are not compatible with sqlalchemy 2
-        run: poetry remove snowflake-sqlalchemy sqlalchemy-exasol
-
-      - name: add sqlalchemy 2
-        run: poetry add --lock --optional 'sqlalchemy>=2,<3'
-
-      - name: checkout the lock file
-        run: git checkout poetry.lock
-
-      - name: lock with no updates
-        # poetry add is aggressive and will update other dependencies like
-        # numpy and pandas so we keep the pyproject.toml edits and then relock
-        # without updating anything except the requested versions
-        run: poetry lock --no-update
-
-      - name: check the sqlalchemy version
-        run: poetry show sqlalchemy --no-ansi | grep version | cut -d ':' -f2- | sed 's/ //g' | grep -P '^2\.'
-
-      - name: upload deps file
-        uses: actions/upload-artifact@v3
-        with:
-          name: deps
-          path: |
-            pyproject.toml
-            poetry.lock
-
   test_backends_sqlalchemy2:
     name: SQLAlchemy 2 ${{ matrix.backend.title }} ${{ matrix.os }} python-${{ matrix.python-version }}
     runs-on: ${{ matrix.os }}
-    needs:
-      - gen_lockfile_sqlalchemy2
     strategy:
       fail-fast: false
       matrix:
@@ -708,37 +666,23 @@ jobs:
         if: matrix.backend.services != null
         run: docker compose up --wait ${{ join(matrix.backend.services, ' ') }}
 
+      - name: install poetry
+        run: pipx install 'poetry==1.7.1'
+
       - name: install python
         uses: actions/setup-python@v5
         id: install_python
         with:
           python-version: ${{ matrix.python-version }}
 
-      - name: download poetry lockfile
-        uses: actions/download-artifact@v3
-        with:
-          name: deps
-          path: deps
-
-      - name: pull out lockfile
-        run: |
-          set -euo pipefail
-
-          mv -f deps/* .
-          rm -r deps
-
-      - uses: syphar/restore-virtualenv@v1
-        with:
-          requirement_files: poetry.lock
-          custom_cache_key_element: ${{ matrix.backend.name }}-${{ steps.install_python.outputs.python-version }}
+      - name: remove deps that are not compatible with sqlalchemy 2
+        run: poetry remove snowflake-sqlalchemy sqlalchemy-exasol
 
-      - uses: syphar/restore-pip-download-cache@v1
-        with:
-          requirement_files: poetry.lock
-          custom_cache_key_element: ${{ steps.install_python.outputs.python-version }}
+      - name: add sqlalchemy 2
+        run: poetry update sqlalchemy
 
-      - name: install poetry
-        run: python -m pip install --upgrade pip 'poetry==1.7.1'
+      - name: check sqlalchemy is version 2
+        run: poetry run python -c 'import sqlalchemy as sa; assert sa.__version__[0] == "2", sa.__version__'
 
       - name: install ibis
         run: poetry install --without dev --without docs --extras "${{ join(matrix.backend.extras, ' ') }}"