Add emoji to README.

PiperOrigin-RevId: 535670105
Change-Id: Ic9bf3e029eb5db8aa30a48c64d3f0d5fdb814f89

README.md

@@ -135,7 +135,7 @@ to list here individually. Below we focus on bindings and converters.
 
 These packages give users of various languages access to MuJoCo functionality:
 
-#### First-party bindings
+#### First-party bindings:
 
 - [Python bindings](https://mujoco.readthedocs.io/en/stable/python.html)
   - [dm_control](https://github.com/deepmind/dm_control), DeepMind's related
@@ -143,13 +143,13 @@ These packages give users of various languages access to MuJoCo functionality:
   a module for procedural manipulation of MuJoCo models.
 - [C# bindings and Unity plug-in](https://mujoco.readthedocs.io/en/stable/unity.html)
 
-#### Third-party bindings
+#### Third-party bindings:
 
 - **WebAssembly**: [mujoco_wasm](https://github.com/zalo/mujoco_wasm) by [@zalo](https://github.com/zalo) with contributions by
   [@kevinzakka](https://github.com/kevinzakka), based on the [emscripten build](https://github.com/stillonearth/MuJoCo-WASM) by
   [@stillonearth](https://github.com/stillonearth).
 
-  [Click here](https://zalo.github.io/mujoco_wasm/) for a live demo of MuJoCo running in your browser.
+  :arrow_right: [Click here](https://zalo.github.io/mujoco_wasm/) for a live demo of MuJoCo running in your browser.
 - **Swift**: [swift-mujoco](https://github.com/liuliu/swift-mujoco)
 - **Java**: [mujoco-java](https://github.com/CommonWealthRobotics/mujoco-java)
 - **Julia**: [Lyceum](https://github.com/Lyceum/MuJoCo.jl) (unmaintained)