ci: install rustfmt and clippy for the toolchain

Without a rust-toolchain file the action installs a minimal stable,
which carries neither component; the format step failed on the first
push. Name the two the job uses.

.gitea/workflows/ci.yml

@@ -13,7 +13,11 @@ jobs:
     steps:
       - uses: https://gitea.com/actions/checkout@v4
 
+      # Without a rust-toolchain file this installs a minimal stable,
+      # which carries neither component; the job uses both.
       - uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          components: rustfmt, clippy
 
       - name: Format
         run: cargo fmt --all -- --check