Fix spx Linux x64 url (#17)

Author: ab-10

docs/spx/index.mdx

@@ -25,7 +25,7 @@ Before using spx, ensure you have:
 
 Download the appropriate binary for your system architecture:
 
-- **Linux x64:** [linux-x64](https://storage.googleapis.com/docs-recurse-ml/spx/spx-darwin-x64/spx)
+- **Linux x64:** [linux-x64](https://storage.googleapis.com/docs-recurse-ml/spx/spx-linux-x64/spx)
 - **Linux ARM64:** [linux-arm64](https://storage.googleapis.com/docs-recurse-ml/spx/spx-linux-arm64/spx)
 - **Linux x64 (musl):** [linux-x64-musl](https://storage.googleapis.com/docs-recurse-ml/spx/spx-linux-x64-musl/spx)
 - **Linux ARM64 (musl):** [linux-arm64-musl](https://storage.googleapis.com/docs-recurse-ml/spx/spx-linux-arm64-musl/spx)