doc(backup):add notes to the backup docs

docs/LCM/backup-minio-data.md

@@ -1,6 +1,8 @@
 # Backup Minio data
 
-Documentation shown here guides you how to backup the Minio data.
+Documentation shown here guides you how to backup the `Minio` data.
+
+>NOTES: The document shown here is for reference only, you can also look for other available data backup alternatives based on your real case.
 
 ## Prerequisites
 

docs/LCM/backup-psql-data.md

@@ -1,6 +1,8 @@
 # Backup Postgresql data
 
-Documentation shown here guides you how to backup the psql database data.
+Documentation shown here guides you how to backup the `Postgresql` database data.
+
+>NOTES: The document shown here is for reference only, you can also look for other available data backup alternatives based on your real case.
 
 ## get postgresql username and password from secret
 

docs/LCM/backup-redis-data.md

@@ -1,6 +1,8 @@
 # Backup Redis data
 
-Documentation shown here guides you how to backup the Redis data.
+Documentation shown here guides you how to backup the `Redis` data.
+
+>NOTES: The document shown here is for reference only, you can also look for other available data backup alternatives based on your real case.
 
 ## Step 1