Use only GitHub-owned actions in the test workflow

The org's Actions policy blocks dtolnay/rust-toolchain and
Swatinem/rust-cache (startup_failure). Install toolchains with the
preinstalled rustup instead and cache with actions/cache.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: bouk

.github/workflows/test.yml

@@ -18,8 +18,14 @@ jobs:
         os: [ubuntu-latest, macos-latest, windows-latest]
     steps:
       - uses: actions/checkout@v7
-      - uses: dtolnay/rust-toolchain@stable
-      - uses: Swatinem/rust-cache@v2
+      - run: rustup update stable && rustup default stable
+      - uses: actions/cache@v6
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: test-${{ matrix.os }}-${{ hashFiles('**/Cargo.toml') }}
       - run: cargo test
       - run: cargo test --features serialization
       - run: cargo test --release --features serialization
@@ -32,19 +38,31 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v7
-      - uses: dtolnay/rust-toolchain@nightly
+      - run: |
+          rustup toolchain install nightly --profile minimal --component miri
+          rustup default nightly
+      - uses: actions/cache@v6
         with:
-          components: miri
-      - uses: Swatinem/rust-cache@v2
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: miri-${{ hashFiles('**/Cargo.toml') }}
       - run: cargo miri test
 
   wasm32:
     name: wasm32 build
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v7
-      - uses: dtolnay/rust-toolchain@stable
+      - run: |
+          rustup update stable && rustup default stable
+          rustup target add wasm32-unknown-unknown
+      - uses: actions/cache@v6
         with:
-          targets: wasm32-unknown-unknown
-      - uses: Swatinem/rust-cache@v2
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: wasm32-${{ hashFiles('**/Cargo.toml') }}
       - run: cargo build --release --target wasm32-unknown-unknown