ci: switch clippy toolchain from stable to beta

fix(ipdb): add #[expect(clippy::collapsible_if)] to improve linting

.github/workflows/ci.yml

@@ -403,10 +403,10 @@ jobs:
           persist-credentials: false
       - uses: actions-rust-lang/setup-rust-toolchain@v1
         with:
-          toolchain: stable
+          toolchain: beta
           components: clippy
           cache-key: x86_64-unknown-linux-gnu
-      - run: cargo +stable clippy --all-targets ${{ matrix.features }} -- -Dwarnings
+      - run: cargo +beta clippy --all-targets ${{ matrix.features }} -- -Dwarnings
   pre-commit:
     runs-on: ubuntu-24.04
     steps:

src/ipdb.rs

@@ -122,6 +122,7 @@ impl DbType {
     ) -> color_eyre::Result<()> {
         let db_path = self.db_path().await?;
         let mut headers = reqwest::header::HeaderMap::new();
+        #[expect(clippy::collapsible_if)]
         if tokio::fs::metadata(&db_path).await.is_ok_and(|m| m.is_file()) {
             if let Some(etag) =
                 self.read_etag().await.wrap_err("failed to read ETag")?