Fix Chip-tool heap memory increase in interactive mode (#33838)

Author: joonhaengHeo

src/controller/ExamplePersistentStorage.cpp

@@ -85,6 +85,7 @@ CHIP_ERROR PersistentStorage::Init(const char * name, const char * directory)
 
     mName      = name;
     mDirectory = directory;
+    mConfig.clear();
     mConfig.parse(ifs);
     ifs.close();