CI: Use Rust 1.80

.github/workflows/rust.yml

@@ -15,8 +15,13 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
+    - uses: dtolnay/rust-toolchain@master
+      with:
+        toolchain: "1.80"
+
     - name: Build
       run: cargo build --verbose
+
     - name: Run tests
       run: cargo test --verbose -- --include-ignored