CHANGE: Change extension of project-wide template asset to .json (#1772)

* Change extension of project-wide template asset to .json

This way the template asset is not picked up by Editor views.

* Update CHANGELOG

Author: jfreire-unity

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -17,6 +17,7 @@ however, it has to be formatted properly to pass verification tests.
 - Static analysis warnings regarding flag enums have been suppressed in order to avoid compile-time warnings or errors.
 - Action Map and Action Tree views of the UI Toolkit based Input Action Editor now prevents deselection in both views when Escape key is pressed.
 - Input Action Asset editors Auto-save feature has been modified to trigger on focus-lost when activated instead of triggering on every modification to the asset in order to reduce impact of processing required to handle modified assets.
+- Project-wide input actions template extension changed from .inputactions to .json. This avoids showing template actions in the action's selector UI that are not intended to be used.
 
 ### Added
 - Support for [Game rotation vector](https://developer.android.com/reference/android/hardware/Sensor#TYPE_GAME_ROTATION_VECTOR) sensor on Android

Packages/com.unity.inputsystem/InputSystem/Editor/ProjectWideActions/ProjectWideActionsAsset.cs

@@ -10,7 +10,7 @@ namespace UnityEngine.InputSystem.Editor
 {
     internal static class ProjectWideActionsAsset
     {
-        internal const string kDefaultAssetPath = "Packages/com.unity.inputsystem/InputSystem/Editor/ProjectWideActions/ProjectWideActionsTemplate.inputactions";
+        internal const string kDefaultAssetPath = "Packages/com.unity.inputsystem/InputSystem/Editor/ProjectWideActions/ProjectWideActionsTemplate.json";
         internal const string kAssetPath = "ProjectSettings/InputManager.asset";
         internal const string kAssetName = InputSystem.kProjectWideActionsAssetName;