[chore] Change comment on `bucket_counts` to reflect spec.

See https://opentelemetry.io/docs/reference/specification/metrics/data-model/#exponential-buckets

opentelemetry/proto/metrics/v1/metrics.proto

@@ -536,9 +536,9 @@ message ExponentialHistogramDataPoint {
     // Note: This uses a varint encoding as a simple form of compression.
     sint32 offset = 1;
 
-    // Count is an array of counts, where count[i] carries the count
-    // of the bucket at index (offset+i).  count[i] is the count of
-    // values greater than base^(offset+i) and less or equal to than
+    // BucketCounts is an array of count values, where BucketCounts[i] carries
+    // the count of the bucket at index (offset+i). BucketCounts[i] is the count
+    // of values greater than base^(offset+i) and less than or equal to
     // base^(offset+i+1).
     //
     // Note: By contrast, the explicit HistogramDataPoint uses