Update DeterminateSystems/magic-nix-cache-action action to v12

.gitea/workflows/build.yml

@@ -18,7 +18,7 @@ jobs:
         uses: cachix/install-nix-action@v31
 
     #  - uses: DeterminateSystems/nix-installer-action@v4
-      - uses: DeterminateSystems/magic-nix-cache-action@v11
+      - uses: DeterminateSystems/magic-nix-cache-action@v12
       - uses: DeterminateSystems/flake-checker-action@v11
 
       - name: "Install Cachix ❄️"

.gitea/workflows/update.yml

@@ -15,7 +15,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
       - name: Install nix
-        uses: DeterminateSystems/nix-installer-action@v18
+        uses: DeterminateSystems/nix-installer-action@v17
         with:
           github-token: ${{ secrets.GH_TOKEN_FOR_UPDATES }}
           extra_nix_config: |