Re-enable macOS x86_64 cross-compile target

Deno 2.6.4 fixes the regression bug that caused cross-compilation to
x86_64-apple-darwin to fail. This reverts the workaround from
ecc823d.

denoland/deno#31664 (comment)

Author: dahlia

.github/actions/setup-deno/action.yaml

@@ -6,4 +6,4 @@ runs:
   steps:
   - uses: denoland/setup-deno@v2
     with:
-      deno-version: 2.6.3  # Keep in sync with mise.toml
+      deno-version: 2.6.4  # Keep in sync with mise.toml