chore(deps): update determinatesystems/nix-installer-action action to v7 (#77)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/test-flakes-project.yml

@@ -26,7 +26,7 @@ jobs:
       uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4
 
     - name: Install Nix
-      uses: DeterminateSystems/nix-installer-action@bc7b19257469c8029b46f45ac99ecc11156c8b2d # v6
+      uses: DeterminateSystems/nix-installer-action@5620eb4af6b562c53e4d4628c0b6e4f9d9ae8612 # v7
 
     - name: Set up Magic Nix Cache
       uses: DeterminateSystems/magic-nix-cache-action@8a218f9e264e9c3803c9a1ee1c30d8e4ab55be63 # v2

.github/workflows/update-flake-lock.yml

@@ -17,7 +17,7 @@ jobs:
         token: ${{ secrets.github-token }}
 
     - name: Install Nix
-      uses: DeterminateSystems/nix-installer-action@bc7b19257469c8029b46f45ac99ecc11156c8b2d # v6
+      uses: DeterminateSystems/nix-installer-action@5620eb4af6b562c53e4d4628c0b6e4f9d9ae8612 # v7
 
     - name: Update flake.lock and push
       shell: bash