feat(io-gcp-bigquery): Add log for direct read quota exceeded retries (#36717)

When a BigQuery direct read operation exceeds its quota, it returns a `RESOURCE_EXHAUSTED` error with retry information. The system correctly handles this by retrying the operation after a delay.

This commit adds an informational log message to make this specific retry event more visible. This helps in diagnosing performance issues or understanding why a job might be experiencing delays, as it explicitly indicates that retries are occurring due to quota limitations.

Author: liferoad

sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigquery/BigQueryServicesImpl.java

@@ -1838,6 +1838,7 @@ public void onRetryAttempt(Status status, Metadata metadata) {
             && status.getCode() == Code.RESOURCE_EXHAUSTED
             && metadata != null
             && metadata.containsKey(KEY_RETRY_INFO)) {
+          LOG.info("BigQuery direct read quota exceeded, retrying.");
           RetryInfo retryInfo = metadata.get(KEY_RETRY_INFO);
           if (retryInfo.hasRetryDelay()) {
             long delay =