fix: fix connectivity error count calculation (#1632)

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Fixes #<issue_number_goes_here> ☕️

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Author: mutianf

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/stub/metrics/BuiltinMetricsTracer.java

@@ -71,9 +71,6 @@ class BuiltinMetricsTracer extends BigtableTracer {
   private String zone = "global";
   private String cluster = "unspecified";
 
-  // gfe stats
-  private AtomicLong gfeMissingHeaders = new AtomicLong(0);
-
   @VisibleForTesting
   BuiltinMetricsTracer(
       OperationType operationType, SpanName spanName, StatsRecorderWrapper recorder) {
@@ -208,10 +205,10 @@ public void recordGfeMetadata(@Nullable Long latency, @Nullable Throwable throwa
     // zone information
     if (latency != null) {
       recorder.putGfeLatencies(latency);
+      recorder.putGfeMissingHeaders(0);
     } else {
-      gfeMissingHeaders.incrementAndGet();
+      recorder.putGfeMissingHeaders(1);
     }
-    recorder.putGfeMissingHeaders(gfeMissingHeaders.get());
   }
 
   @Override

google-cloud-bigtable/src/test/java/com/google/cloud/bigtable/data/v2/stub/metrics/BuiltinMetricsTracerTest.java

@@ -244,7 +244,7 @@ public void testGfeMetrics() {
     // The first time the request was retried, it'll increment missing header counter
     verify(statsRecorderWrapper, times(fakeService.getAttemptCounter().get()))
         .putGfeMissingHeaders(gfeMissingHeaders.capture());
-    assertThat(gfeMissingHeaders.getValue()).isEqualTo(1);
+    assertThat(gfeMissingHeaders.getAllValues()).containsExactly(1L, 0L);
 
     assertThat(status.getAllValues()).containsExactly("UNAVAILABLE", "OK");
     assertThat(tableId.getAllValues()).containsExactly(TABLE_ID, TABLE_ID);