chore: add cli and dependencies installation to CI steps (#280)

Co-authored-by: Michael Dombrowski <mdombro@amazon.com>

.github/workflows/CI.yml

@@ -38,10 +38,14 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
-      - name: Python version
+      - name: Install CLI and dependencies
         run: |
           python -VV
           python -m pip install --upgrade pip
+          # Perform clean install without test dependencies to ensure none of test dependencies
+          # have been used in the gdk codebase.
+          pip install .
+          gdk --help
       - name: Lint with flake8
         run: |
           pip install flake8