rename dubbo-ops to dubbo-admin (#3628)

CHANGES.md

@@ -20,7 +20,7 @@ Please check [here](https://github.com/apache/incubator-dubbo/blob/2.7.0-release
 
 - Simplified registry URL. With lower Registry memory use and less notification pressure from Service Directory, separates Configuration notification from Service Discovery.
 
-- Metadata Center. A totally new concept since 2.7.0,  used to store service metadata including static configuration, service definition, method signature, etc.. By default, Zookeeper and Redis are supported as the backend storage. Will work as the basis of service testing, mock and other service governance features going to be supported in OPS.
+- Metadata Center. A totally new concept since 2.7.0,  used to store service metadata including static configuration, service definition, method signature, etc.. By default, Zookeeper and Redis are supported as the backend storage. Will work as the basis of service testing, mock and other service governance features going to be supported in [Dubbo-Admin](https://github.com/apache/incubator-dubbo-admin).
 
 - Asynchronous Programming Model (only works for Dubbo protocol now)
   - Built-in support for the method with CompletableFuture<T> signature.

README.md

@@ -209,7 +209,7 @@ See [CONTRIBUTING](https://github.com/apache/incubator-dubbo/blob/master/CONTRI
   * blog post
   * translation on documentation
   * use cases about how Dubbo is being used in enterprise system.
-* Improve the [dubbo-ops/dubbo-monitor](https://github.com/apache/incubator-dubbo-ops).
+* Improve the [dubbo-admin/dubbo-monitor](https://github.com/apache/incubator-dubbo-admin).
 * Contribute to the projects listed in [ecosystem](https://github.com/dubbo).
 * Any form of contribution that is not mentioned above.
 * If you would like to contribute, please send an email to dev@dubbo.incubator.apache.org to let us know!
@@ -228,7 +228,7 @@ Please report security vulnerability to [us](mailto:security@dubbo.incubator.apa
 * [Dubbo Website](https://github.com/apache/incubator-dubbo-website) - Apache Dubbo (incubating) official website
 * [Dubbo Samples](https://github.com/apache/incubator-dubbo-samples) - samples for Apache Dubbo (incubating)
 * [Dubbo Spring Boot](https://github.com/apache/incubator-dubbo-spring-boot-project) - Spring Boot Project for Dubbo
-* [Dubbo OPS](https://github.com/apache/incubator-dubbo-ops) - The reference implementation for Dubbo admin
+* [Dubbo Admin](https://github.com/apache/incubator-dubbo-admin) - The reference implementation for Dubbo admin
 
 #### Language