Fix the description under timeout isn't translated completely

Reuse existing string instead of using new string for one-handed
timeout description.

Bug: 159298092

Test: manual
Change-Id: I903998dc58218f67d37fa449ef1a6a0615637bb5

tests/robotests/src/com/android/settings/gestures/OneHandedTimeoutPreferenceControllerTest.java

@@ -103,7 +103,7 @@ public class OneHandedTimeoutPreferenceControllerTest {
                 OneHandedSettingsUtils.OneHandedTimeout.SHORT.getValue());
 
         assertThat(mController.getSummary()).isEqualTo(String.format(
-                mContext.getResources().getString(R.string.one_handed_timeout_summary),
+                mContext.getResources().getString(R.string.screen_timeout_summary),
                 timeoutTitles[OneHandedSettingsUtils.OneHandedTimeout.SHORT.ordinal()]));
     }
 }