fix:fix [Deserialization of Untrusted Data in logback](https://github.com/Tencent/spring-cloud-tencent/security/dependabot/1).

pom.xml

@@ -76,12 +76,23 @@
         <!-- Spring Cloud -->
         <spring.cloud.version>Hoxton.SR9</spring.cloud.version>
 
+        <!-- Dependencies -->
+        <logback.version>1.2.7</logback.version>
+
         <!-- Maven Plugin Versions -->
         <jacoco.version>0.8.3</jacoco.version>
         <maven-source-plugin.version>3.2.0</maven-source-plugin.version>
         <flatten-maven-plugin.version>1.2.7</flatten-maven-plugin.version>
     </properties>
 
+    <dependencies>
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <version>${logback.version}</version>
+        </dependency>
+    </dependencies>
+
     <dependencyManagement>
         <dependencies>
             <!-- Spring Boot Dependencies -->
@@ -232,16 +243,16 @@
         </profile>
     </profiles>
 
-    <repositories>
-        <repository>
-            <id>nexus-snapshots</id>
-            <url>https://oss.sonatype.org/content/repositories/snapshots/</url>
-            <releases>
-                <enabled>false</enabled>
-            </releases>
-            <snapshots>
-                <enabled>true</enabled>
-            </snapshots>
-        </repository>
-    </repositories>
+    <!--    <repositories>-->
+    <!--        <repository>-->
+    <!--            <id>nexus-snapshots</id>-->
+    <!--            <url>https://oss.sonatype.org/content/repositories/snapshots/</url>-->
+    <!--            <releases>-->
+    <!--                <enabled>false</enabled>-->
+    <!--            </releases>-->
+    <!--            <snapshots>-->
+    <!--                <enabled>true</enabled>-->
+    <!--            </snapshots>-->
+    <!--        </repository>-->
+    <!--    </repositories>-->
 </project>

spring-cloud-tencent-examples/polaris-circuitbreaker-example/polaris-circuitbreaker-example-a/pom.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <parent>
         <artifactId>polaris-circuitbreaker-example</artifactId>
@@ -17,12 +17,6 @@
     </properties>
 
     <dependencies>
-        <dependency>
-            <groupId>ch.qos.logback</groupId>
-            <artifactId>logback-core</artifactId>
-            <version>1.2.3</version>
-            <scope>compile</scope>
-        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>

spring-cloud-tencent-examples/polaris-circuitbreaker-example/polaris-circuitbreaker-example-b/pom.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <parent>
         <artifactId>polaris-circuitbreaker-example</artifactId>
@@ -17,12 +17,6 @@
     </properties>
 
     <dependencies>
-        <dependency>
-            <groupId>ch.qos.logback</groupId>
-            <artifactId>logback-core</artifactId>
-            <version>1.2.3</version>
-            <scope>compile</scope>
-        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-webflux</artifactId>