download cpu version of torchmetrics for testing (#134)

* download cpu version of torchmetrics for testing

* remove cache pip

Author: jshin1394

.github/workflows/ci.yml

@@ -15,16 +15,10 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: 3.12
-      - name: Cache pip dependencies
-        uses: actions/cache@v3
-        with:
-          path: ~/.cache/pip
-          key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
-          restore-keys: |
-            ${{ runner.os }}-pip-
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
+          pip install torch --index-url https://download.pytorch.org/whl/cpu
           pip install ".[dev]"
       - name: Run Unit Tests
         run: |