add chmod +x cmd to deweb local server docs

docs/deweb/getting-started/setup-local-server.mdx

@@ -52,7 +52,13 @@ For Linux users, running binaries via GUI can vary greatly depending on the desk
 
 1. Open your terminal (command prompt on Windows).
 2. Navigate to the directory where the binary is located.
-3. Run the server with the following command:
+3. Run the following command to allow execution permission:
+
+```bash
+   chmod +x deweb-server
+```
+
+4. Run the server with the following command:
    ```bash
    ./deweb-server
    ```