[privacy_budget] Fix use-after-move in scoped_identifiability_test_sample_collector

Fix use-after-move (potential) bugs found by the
"bugprone-use-after-move" clang-tidy check.

Bug: 1122844
Change-Id: I521dc064f7ae4522b25a3c7c003d608616acba05
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2401521
Commit-Queue: Asanka Herath <asanka@chromium.org>
Reviewed-by: Asanka Herath <asanka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#806159}

third_party/blink/common/privacy_budget/scoped_identifiability_test_sample_collector.cc

@@ -29,7 +29,7 @@ void ScopedIdentifiabilityTestSampleCollector::Record(
     std::vector<IdentifiableSample> metrics) {
   entries_.emplace_back(source, std::move(metrics));
   AggregatingSampleCollector::UkmMetricsContainerType metrics_map;
-  for (auto metric : metrics) {
+  for (auto metric : entries_.back().metrics) {
     metrics_map.emplace(metric.surface.ToUkmMetricHash(),
                         metric.value.ToUkmMetricValue());
   }