Adding 1s time gap between slot1 & slot2 setDataThrottling tests

  Modem has restriction that it can not process back-to-back thermal actions.
  For DSDS device, after slot-1 test finished, a 1s delay is needed before start slot-2 test.

Bug: 187968151
Test: atest VtsHalRadioV1_6TargetTest -- --test-arg com.android.tradefed.testtype.GTest:native-test-flag:"--gtest_filter=*setDataThrottling*"
Change-Id: I052d0d9c7c0ccc86a7590204679295268973c6cf
diff --git a/radio/1.6/vts/functional/radio_hidl_hal_api.cpp b/radio/1.6/vts/functional/radio_hidl_hal_api.cpp
index 7c05984..27e641a 100644
--- a/radio/1.6/vts/functional/radio_hidl_hal_api.cpp
+++ b/radio/1.6/vts/functional/radio_hidl_hal_api.cpp
@@ -498,6 +498,8 @@
                  ::android::hardware::radio::V1_6::RadioError::NONE,
                  ::android::hardware::radio::V1_6::RadioError::INVALID_ARGUMENTS}));
     }
+
+    sleep(1);
 }
 
 /*