feat: cache more cargo binaries

Instead of relying on `.crates2.json` to know which binaries are installed,
scan the bin directory and save the result in the action's state.

.github/workflows/binstall.yml

@@ -0,0 +1,34 @@
+name: binstall
+
+on: [push, pull_request]
+
+permissions: {}
+
+jobs:
+  binstall:
+    if: github.repository == 'Swatinem/rust-cache'
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+
+    name: Test `cargo binstall` on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+
+    env:
+      CARGO_TERM_COLOR: always
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - run: rustup toolchain install stable --profile minimal --no-self-update
+
+      - uses: cargo-bins/cargo-binstall@v1.17.9
+
+      - uses: ./
+
+      - run: cargo binstall -y cargo-deny
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}