fix: align error parsing

Author: alespour

src/main/java/com/influxdb/v3/client/internal/RestClient.java

@@ -299,9 +299,13 @@ private String formatErrorMessage(@Nonnull final String body, @Nullable final St
 
             // Core/Enterprise object format:
             // {"error":"...","data":{"error_message":"..."}}
-            final String errorMessage = errNonEmptyField(dataNode, "error_message");
-            if (errorMessage != null) {
-                return errorMessage;
+            if (isV3PartialWriteError(error) && dataNode != null && dataNode.isObject()) {
+                final StringBuilder message = new StringBuilder(error);
+                final String errorMessage = errNonEmptyField(dataNode, "error_message");
+                if (errorMessage != null) {
+                    message.append(":\n\t").append(errorMessage);
+                }
+                return message.toString();
             }
 
             return error;

src/test/java/com/influxdb/v3/client/internal/RestClientTest.java

@@ -551,7 +551,8 @@ public void errorFromBodyV3WithDataObject() { // Core/Enterprise object format
       Assertions.assertThat(thrown)
               .isInstanceOf(InfluxDBPartialWriteException.class)
               .isInstanceOf(InfluxDBApiHttpException.class)
-              .hasMessage("HTTP status code: 400; Message: invalid field value");
+              .hasMessage("HTTP status code: 400; Message: parsing failed for write_lp endpoint:\n"
+                      + "\tinvalid field value");
 
       InfluxDBPartialWriteException partialWriteException = (InfluxDBPartialWriteException) thrown;
       Assertions.assertThat(partialWriteException.statusCode()).isEqualTo(400);