Update GitHub workflow actions.

Author: brocaar

.github/workflows/main.yml

@@ -13,15 +13,15 @@ jobs:
     steps:
       -
         name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - 
         name: Install Nix
         uses: cachix/install-nix-action@v31
         with:
-          nix_path: nixpkgs=channel:nixos-25.05
+          nix_path: nixpkgs=channel:nixos-25.11
       -
         name: Cargo cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~/.cargo/bin/
@@ -41,15 +41,15 @@ jobs:
     steps:
       -
         name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - 
         name: Install Nix
         uses: cachix/install-nix-action@v31
         with:
-          nix_path: nixpkgs=channel:nixos-25.05
+          nix_path: nixpkgs=channel:nixos-25.11
       -
         name: Cargo cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~/.cargo/bin/