ci: bump DeterminateSystems/nix-installer-action from 15 to 16

Bumps [DeterminateSystems/nix-installer-action](https://github.com/determinatesystems/nix-installer-action) from 15 to 16.
- [Release notes](https://github.com/determinatesystems/nix-installer-action/releases)
- [Commits](DeterminateSystems/nix-installer-action@v15...v16)

---
updated-dependencies:
- dependency-name: DeterminateSystems/nix-installer-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/ci.yaml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - uses: DeterminateSystems/nix-installer-action@v15
+    - uses: DeterminateSystems/nix-installer-action@v16
     - uses: cachix/cachix-action@v15
       with:
         name: otavio-nix-config
@@ -36,7 +36,7 @@ jobs:
           - poirot
     steps:
     - uses: actions/checkout@v4
-    - uses: DeterminateSystems/nix-installer-action@v15
+    - uses: DeterminateSystems/nix-installer-action@v16
     - uses: cachix/cachix-action@v15
       with:
         name: otavio-nix-config
@@ -54,7 +54,7 @@ jobs:
           - "otavio@generic-x86"
     steps:
     - uses: actions/checkout@v4
-    - uses: DeterminateSystems/nix-installer-action@v15
+    - uses: DeterminateSystems/nix-installer-action@v16
     - uses: cachix/cachix-action@v15
       with:
         name: otavio-nix-config

.github/workflows/update-flake.yaml

@@ -11,7 +11,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
       - name: Install Nix
-        uses: DeterminateSystems/nix-installer-action@v15
+        uses: DeterminateSystems/nix-installer-action@v16
       - name: Update flake.lock
         uses: DeterminateSystems/update-flake-lock@v24
         with: