Throw away initial measurements before interval tests

Bug: 264597734
Test: atest VtsHalGnssTargetTest
Change-Id: I1064807adf3264f13c1ef6678df37cff350503c5
diff --git a/gnss/aidl/vts/gnss_hal_test.cpp b/gnss/aidl/vts/gnss_hal_test.cpp
index 7578585..fb9af52 100644
--- a/gnss/aidl/vts/gnss_hal_test.cpp
+++ b/gnss/aidl/vts/gnss_hal_test.cpp
@@ -456,6 +456,7 @@
                                               const int numMeasurementEvents,
                                               const int timeoutSeconds,
                                               std::vector<int>& deltasMs) {
+    callback->gnss_data_cbq_.reset();  // throw away the initial measurements if any
     int64_t lastElapsedRealtimeMillis = 0;
     for (int i = 0; i < numMeasurementEvents; i++) {
         GnssData lastGnssData;