Add sleep to ShouldReportStats Test in libinput_tests

Tests were flaky previously, by adding this sleep, this should should
assert that stats.shouldReport() is always true.

Test: atest LatencyStatisticsTest
Bug: 139050511
Change-Id: I9ca106fca758378eded19c6bf130aaee5387967c
Signed-off-by: Atif Niyaz <atifniyaz@google.com>
diff --git a/libs/input/tests/LatencyStatistics_test.cpp b/libs/input/tests/LatencyStatistics_test.cpp
index 6d1cab4..eb12d4e 100644
--- a/libs/input/tests/LatencyStatistics_test.cpp
+++ b/libs/input/tests/LatencyStatistics_test.cpp
@@ -18,6 +18,7 @@
 #include <input/LatencyStatistics.h>
 #include <cmath>
 #include <limits>
+#include <thread>
 
 namespace android {
 namespace test {
@@ -65,6 +66,8 @@
     LatencyStatistics stats{0min};
     stats.addValue(5.0);
 
+    std::this_thread::sleep_for(1us);
+
     ASSERT_EQ(stats.shouldReport(), true);
 }