Update Reference Sidecar Implementation Version

Bug: b/201579002
Test: atest CtsWindowManagerJetpackTestCases:SidecarTest
Test: atest CtsWindowManagerJetpackTestCases:ExtensionWindowLayoutComponentTest
Test: [Manual] On a device that only has Sidecar, run an app that uses
      the WindowManager Jetpack library (for example, YouTube) and verify
      that the app features that use the library work as expected.
Change-Id: I2e15cf06b6a7af33b22b52263fbe084982db8df2

libs/WindowManager/Jetpack/src/androidx/window/sidecar/SidecarProvider.java

@@ -36,6 +36,6 @@ public class SidecarProvider {
      * @return API version string in MAJOR.MINOR.PATCH-description format.
      */
     public static String getApiVersion() {
-        return "0.1.0-settings_sample";
+        return "1.0.0-reference";
     }
 }