chore(ci): install a pre-release version of Cross

Author: yvt

.github/workflows/release.yml

@@ -100,6 +100,14 @@ jobs:
           target: ${{ matrix.target }}
           override: true
 
+      # Install a pre-release version of Cross
+      # TODO: We need to pre-install Cross because we need cross-rs/cross#591 to
+      #       get a newer C++ compiler toolchain. Remove this step when Cross
+      #       0.3.0, which includes cross-rs/cross#591, is released.
+      - name: Install Cross
+        if: "matrix.cross"
+        run: cargo install cross --git https://github.com/cross-rs/cross.git --rev 47df5c76e7cba682823a0b6aa6d95c17b31ba63a
+
       - name: Run cargo test
         uses: actions-rs/cargo@v1
         if: "!matrix.skip_tests"