Use http_archive for buck crates without vendoring

.gitattributes

@@ -1,2 +1,2 @@
-third-party/BUCK linguist-generated
+# third-party/BUCK linguist-generated
 third-party/bazel/** linguist-generated

.github/workflows/ci.yml

@@ -79,16 +79,9 @@ jobs:
         with:
           submodules: true
       - uses: dtolnay/rust-toolchain@stable
-      - uses: dtolnay/install@reindeer
       - uses: dtolnay/install@buck2
       - name: Install lld
         run: sudo apt-get install lld
-      - run: cargo vendor --versioned-dirs --locked
-        working-directory: third-party
-      - run: reindeer buckify
-        working-directory: third-party
-      - name: Check reindeer-generated BUCK file up to date
-        run: git diff --exit-code
       - run: buck2 run demo
       - run: buck2 build ...
       - run: buck2 test ...