Upgrade springboot.version to 2.6.4

Signed-off-by: liaozan <378024053@qq.com>

pom.xml

@@ -32,7 +32,7 @@
     </developers>
 
     <properties>
-        <springboot.version>2.6.3</springboot.version>
+        <springboot.version>2.6.4</springboot.version>
         <spring.cloud-version>2021.0.1</spring.cloud-version>
 
         <!-- 2th part version -->
@@ -547,4 +547,4 @@
         </pluginRepository>
     </pluginRepositories>
 
-</project>
+</project>
\ No newline at end of file