revert chore: Running pull-gapic-grpc to refresh Gapic layer for datastore gapic upgrade

Author: cindy-peng

google-cloud-datastore/src/main/java/com/google/cloud/datastore/v1/DatastoreSettings.java

@@ -25,6 +25,7 @@
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
 import com.google.api.gax.rpc.ClientSettings;
+import com.google.api.gax.rpc.StubSettings;
 import com.google.api.gax.rpc.TransportChannelProvider;
 import com.google.api.gax.rpc.UnaryCallSettings;
 import com.google.cloud.datastore.v1.stub.DatastoreStubSettings;

google-cloud-datastore/src/main/java/com/google/cloud/datastore/v1/stub/GrpcDatastoreStub.java

@@ -44,6 +44,7 @@
 import io.grpc.MethodDescriptor;
 import io.grpc.protobuf.ProtoUtils;
 import java.io.IOException;
+import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import javax.annotation.Generated;