fix(samples): removed add time from lro. (#530)

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Fixes #<issue_number_goes_here> ☕️

If you write sample code, please follow the [samples format](
https://github.com/GoogleCloudPlatform/java-docs-samples/blob/main/SAMPLE_FORMAT.md).

retail/interactive-tutorials/src/main/java/product/AddFulfillmentPlaces.java

@@ -23,9 +23,7 @@
 import com.google.cloud.ServiceOptions;
 import com.google.cloud.retail.v2.AddFulfillmentPlacesRequest;
 import com.google.cloud.retail.v2.ProductServiceClient;
-import com.google.protobuf.Timestamp;
 import java.io.IOException;
-import java.time.Instant;
 import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 
@@ -47,22 +45,17 @@ public static void main(String[] args) throws IOException, InterruptedException
 
   public static void addFulfillmentPlaces(String productName, String placeId)
       throws IOException, InterruptedException {
-    Timestamp currentDate =
-        Timestamp.newBuilder()
-            .setSeconds(Instant.now().getEpochSecond())
-            .setNanos(Instant.now().getNano())
-            .build();
 
-    System.out.printf("Add fulfilment places with current date: %s", currentDate);
+    System.out.println("Add fulfilment places");
 
     AddFulfillmentPlacesRequest addFulfillmentPlacesRequest =
         AddFulfillmentPlacesRequest.newBuilder()
             .setProduct(productName)
             .setType("pickup-in-store")
             .addPlaceIds(placeId)
-            .setAddTime(currentDate)
             .setAllowMissing(true)
             .build();
+
     System.out.println("Add fulfillment request " + addFulfillmentPlacesRequest);
 
     // Initialize client that will be used to send requests. This client only

retail/interactive-tutorials/src/main/java/product/RemoveFulfillmentPlaces.java

@@ -23,9 +23,7 @@
 import com.google.cloud.ServiceOptions;
 import com.google.cloud.retail.v2.ProductServiceClient;
 import com.google.cloud.retail.v2.RemoveFulfillmentPlacesRequest;
-import com.google.protobuf.Timestamp;
 import java.io.IOException;
-import java.time.Instant;
 import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 
@@ -48,21 +46,17 @@ public static void main(String[] args) throws IOException, InterruptedException
   // remove fulfillment places to product
   public static void removeFulfillmentPlaces(String productName, String storeId)
       throws IOException, InterruptedException {
-    Timestamp currentDate =
-        Timestamp.newBuilder()
-            .setSeconds(Instant.now().getEpochSecond())
-            .setNanos(Instant.now().getNano())
-            .build();
 
-    System.out.printf("Remove fulfilment places with current date: %s", currentDate);
+    System.out.println("Remove fulfilment places with current date");
+
     RemoveFulfillmentPlacesRequest removeFulfillmentRequest =
         RemoveFulfillmentPlacesRequest.newBuilder()
             .setProduct(productName)
             .setType("pickup-in-store")
             .addPlaceIds(storeId)
-            .setRemoveTime(currentDate)
             .setAllowMissing(true)
             .build();
+
     System.out.println("Remove fulfillment request " + removeFulfillmentRequest);
 
     // Initialize client that will be used to send requests. This client only

retail/interactive-tutorials/src/main/java/product/SetInventory.java

@@ -29,9 +29,7 @@
 import com.google.cloud.retail.v2.SetInventoryRequest;
 import com.google.protobuf.FieldMask;
 import com.google.protobuf.Int32Value;
-import com.google.protobuf.Timestamp;
 import java.io.IOException;
-import java.time.Instant;
 import java.util.Arrays;
 import java.util.UUID;
 import java.util.concurrent.TimeUnit;
@@ -57,13 +55,6 @@ public static void setInventory(String productName) throws IOException, Interrup
     float originalPrice = 20.0f;
     float cost = 8.0f;
 
-    // The request timestamp
-    Timestamp requestTime =
-        Timestamp.newBuilder()
-            .setSeconds(Instant.now().getEpochSecond())
-            .setNanos(Instant.now().getNano())
-            .build();
-
     FieldMask setMask =
         FieldMask.newBuilder()
             .addAllPaths(
@@ -97,7 +88,6 @@ public static void setInventory(String productName) throws IOException, Interrup
     SetInventoryRequest setInventoryRequest =
         SetInventoryRequest.newBuilder()
             .setInventory(product)
-            .setSetTime(requestTime)
             .setAllowMissing(true)
             .setSetMask(setMask)
             .build();