chore: simplify Nix setup action (#97)

* chore: simplify nix flake

* fixup! chore: simplify nix flake

Author: pranc1ngpegasus

.github/actions/setup-nix/action.yaml

@@ -1,7 +1,14 @@
 name: setup nix
-description: install Determinate Nix and enable FlakeHub Cache
+description: Install Nix and restore the shared Nix store cache
 runs:
   using: composite
   steps:
-    - uses: DeterminateSystems/determinate-nix-action@4eea0b33e3d1f02ecfe37cf16e7204c424009606 # v3.21.0
-    - uses: DeterminateSystems/flakehub-cache-action@c01e819d047464c3edf6ba778f075952af5a3aa7 # v3.21.0
+    - uses: nixbuild/nix-quick-install-action@9f63be77f412a248c9d9a65a4c82cf066cdf8f0c # v35
+    - uses: nix-community/cache-nix-action@7df957e333c1e5da7721f60227dbba6d06080569 # v7.0.2
+      with:
+        primary-key: nix-v0-${{ runner.os }}-${{ runner.arch }}-${{ hashFiles('**/*.nix', 'flake.lock', '**/Cargo.toml', 'Cargo.lock', 'rust-toolchain.toml') }}
+        restore-prefixes-first-match: nix-v0-${{ runner.os }}-${{ runner.arch }}-
+        purge: true
+        purge-prefixes: nix-v0-${{ runner.os }}-
+        purge-created: 0
+        purge-primary-key: never

.github/workflows/formal.yaml

@@ -11,7 +11,7 @@ permissions:
   id-token: write
 jobs:
   verify:
-    runs-on: ubuntu-slim
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - uses: ./.github/actions/setup-nix