Update CI dependencies to fix failures

Author: oxalica

.github/workflows/ci.yaml

@@ -15,9 +15,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Install Nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@v31
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
       - name: Prepare devShell
@@ -41,10 +41,10 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       # For builtins.
       - name: Install Nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@v31
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
           nix_path: nixpkgs=channel:nixpkgs-unstable
@@ -65,9 +65,9 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Install Nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@v31
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
       - name: Flake check
@@ -84,12 +84,12 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         # flake-compat doesn't support shallow repo.
         with:
           fetch-depth: 0
       - name: Install Nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@v31
         with:
           nix_path: nixpkgs=channel:nixpkgs-unstable
           github_access_token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/future-proof.yaml

@@ -19,9 +19,9 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Install Nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@v31
         with:
           github_access_token: ${{ secrets.GITHUB_TOKEN }}
       - name: Flake update
@@ -40,7 +40,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
       - name: Install cargo-outdated
         uses: dtolnay/install@cargo-outdated
       - name: cargo-outdated