try install nix via action

.gitea/workflows/build.yaml

@@ -10,12 +10,8 @@ jobs:
       - name: Hello
         run: |
           echo "Hello and welcome"
-      - name: Install dependencies
+      - name: Install Nix
-        run: |
+        uses: https://github.com/DeterminateSystems/nix-installer-action@v4
-          curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install linux \
-            --extra-conf "sandbox = false" \
-            --init none \
-            --no-confirm
       - uses: actions/checkout@v3
         name: Checkout
       - name: Metadata