Bump version number to 2.2.1.

PiperOrigin-RevId: 461471944
Change-Id: Ia752d992fabdc57b822bc30b01030c19162917ac

unity/Runtime/Bindings/MujocoBinaryRetriever.cs

@@ -35,7 +35,7 @@ public class MujocoBinaryRetriever {
       if (AssetDatabase.LoadMainAssetAtPath(mujocoPath + "/mujoco.dylib") == null) {
         File.Copy(
             "/Applications/MuJoCo.app/Contents/Frameworks" +
-            "/mujoco.framework/Versions/Current/libmujoco.2.2.0.dylib",
+            "/mujoco.framework/Versions/Current/libmujoco.2.2.1.dylib",
             mujocoPath + "/mujoco.dylib");
         AssetDatabase.Refresh();
       }
@@ -43,7 +43,7 @@ public class MujocoBinaryRetriever {
       if (AssetDatabase.LoadMainAssetAtPath(mujocoPath + "/libmujoco.so") == null) {
         File.Copy(
             Environment.GetFolderPath(Environment.SpecialFolder.UserProfile) +
-            "/.mujoco/mujoco-2.2.0/lib/libmujoco.so.2.2.0",
+            "/.mujoco/mujoco-2.2.1/lib/libmujoco.so.2.2.1",
             mujocoPath + "/libmujoco.so");
         AssetDatabase.Refresh();
       }

unity/Runtime/Bindings/MujocoBindings.cs

@@ -98,7 +98,7 @@ public const int mjMAXLINEPNT = 1000;
 public const int mjMAXPLANEGRID = 200;
 public const bool THIRD_PARTY_MUJOCO_MJXMACRO_H_ = true;
 public const bool THIRD_PARTY_MUJOCO_MUJOCO_H_ = true;
-public const int mjVERSION_HEADER = 220;
+public const int mjVERSION_HEADER = 221;
 
 
 // ------------------------------------Enums------------------------------------

unity/package.json

@@ -1,7 +1,7 @@
 {
   "name": "org.mujoco",
   "displayName": "MuJoCo",
-  "version": "2.1.1",
+  "version": "2.2.1",
   "description": "MuJoCo importer and runtime plug-in",
   "dependencies": {},
   "author": {