ci: remove pnpm cache steps for Forgejo Actions compatibility

.github/workflows/main.yml

@@ -22,20 +22,6 @@ jobs:
         with:
           version: 10
 
-      - name: Get pnpm store directory
-        id: pnpm-cache
-        shell: bash
-        run: |
-          echo "STORE_PATH=$(pnpm store path)" >> $GITHUB_OUTPUT
-
-      - name: Setup pnpm cache
-        uses: actions/cache@v3
-        with:
-          path: ${{ steps.pnpm-cache.outputs.STORE_PATH }}
-          key: ${{ runner.os }}-pnpm-store-${{ hashFiles('**/pnpm-lock.yaml') }}
-          restore-keys: |
-            ${{ runner.os }}-pnpm-store-
-
       - name: Install dependencies
         run: pnpm install --frozen-lockfile