Refactor method name.

apm-collector/apm-collector-grpc-manager/collector-grpc-manager-define/src/main/java/org/skywalking/apm/collector/grpc/manager/service/GRPCManagerService.java

@@ -25,5 +25,5 @@ import org.skywalking.apm.collector.server.Server;
  * @author peng-yongsheng
  */
 public interface GRPCManagerService extends Service {
-    Server getElseCreateServer(String host, int port);
+    Server getOrCreateIfAbsent(String host, int port);
 }

apm-collector/apm-collector-grpc-manager/collector-grpc-manager-provider/src/main/java/org/skywalking/apm/collector/grpc/manager/service/GRPCManagerServiceImpl.java

@@ -38,7 +38,7 @@ public class GRPCManagerServiceImpl implements GRPCManagerService {
         this.servers = servers;
     }
 
-    @Override public Server getElseCreateServer(String host, int port) {
+    @Override public Server getOrCreateIfAbsent(String host, int port) {
         String id = host + String.valueOf(port);
         if (servers.containsKey(id)) {
             return servers.get(id);