finish postTagService and test, modify sth in postService

Change-Id: I76b5982f578b5bffe3c48b0afeda219e01307455
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index 6bde80e..7f85f87 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -1,4 +1,4 @@
-spring.datasource.password=123456
+spring.datasource.password=12345678
 spring.datasource.username=root
 spring.datasource.url=jdbc:mysql://localhost:3306/g8backend
 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver