ci: Install yamlfmt so that yaml formatting can be checked

Author: nicholasbishop

.github/workflows/rust.yml

@@ -88,6 +88,14 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v4
       - uses: Swatinem/rust-cache@v2
+      - name: Install yamlfmt
+        env:
+          YFV: "0.13.0"
+          HASH: "043e96d754a8afa4f4c5c13ffb2f3e50c6be5a70bf53292d3025abc0b42fe4ae"
+        run: |
+          curl -L --fail --output /tmp/yamlfmt.tar.xz https://github.com/google/yamlfmt/releases/download/v${YFV}/yamlfmt_${YFV}_Linux_x86_64.tar.gz
+          echo "${HASH} /tmp/yamlfmt.tar.xz" | sha256sum --check
+          tar xf /tmp/yamlfmt.tar.xz -C /usr/local/bin yamlfmt
       - name: Check formatting
         run: cargo xtask fmt --check
       - name: Run clippy