**Describe the bug**
A clear and concise description of what the bug is.

This reload function has the following problems：

When the client calls reload successfully, the server side reports an error and the configuration of Load does not take effect
```
nanomq reload --conf etc/nanomq.conf
reload succeed
```
When the incoming configuration to be reloaded is as follows, it will directly cause the SERVER print **error: syntax error**

```
auth {
        allow_anonymous = true # add it first, no error
        acl = {include "/etc/nanomq_acl.conf"} # add it next, error report
}
```
Then, the content of /etc/nanomq_acl.conf is default as follows:
```
rules = [
	{"permit": "allow", "username": "#", "action": "subscribe", "topics": ["a/a"]}
	
	# {"permit": "deny", "username": "#", "action": "publish", "topics": ["a/a"]}
	
	# # 允许任何其他发布/订阅操作
	{"permit": "allow"}
]
```
Does nanomq_acl.conf is not supported by the reload function?

**Expected behavior**
A clear and concise description of what you expected to happen.

**Actual Behavior**
Describe what occurred.

**To Reproduce**
If possible include actual reproduction test code here.
Minimal C test cases are perferred.

**Environment Details**
 - NanoMQ v0.21.6-6
 - Operating system and version
 - Compiler and language used
 - testing scenario

**Client SDK**
If possible include the mqtt sdk you used to connect to nanomq
Minimal C test cases are perferred.

**Additional context**
Add any other context about the problem here.

syntax error in nanomq reload
This is a GitHub Issue
repo:nanomq
owner:emqx
Title : syntax error in nanomq reload
Issue date:

--- start body ---
**Describe the bug**
A clear and concise description of what the bug is.

This reload function has the following problems：

When the client calls reload successfully, the server side reports an error and the configuration of Load does not take effect
```
nanomq reload --conf etc/nanomq.conf
reload succeed
```
When the incoming configuration to be reloaded is as follows, it will directly cause the SERVER print **error: syntax error**

```
auth {
        allow_anonymous = true # add it first, no error
        acl = {include "/etc/nanomq_acl.conf"} # add it next, error report
}
```
Then, the content of /etc/nanomq_acl.conf is default as follows:
```
rules = [
	{"permit": "allow", "username": "#", "action": "subscribe", "topics": ["a/a"]}
	
	# {"permit": "deny", "username": "#", "action": "publish", "topics": ["a/a"]}
	
	# # 允许任何其他发布/订阅操作
	{"permit": "allow"}
]
```
Does nanomq_acl.conf is not supported by the reload function?

**Expected behavior**
A clear and concise description of what you expected to happen.

**Actual Behavior**
Describe what occurred.

**To Reproduce**
If possible include actual reproduction test code here.
Minimal C test cases are perferred.

**Environment Details**
 - NanoMQ v0.21.6-6
 - Operating system and version
 - Compiler and language used
 - testing scenario

**Client SDK**
If possible include the mqtt sdk you used to connect to nanomq
Minimal C test cases are perferred.

**Additional context**
Add any other context about the problem here.

--- end body ---
