Error at 'Query files/folders by metadata'

### Description of the issue

In the documentation for "Query files/folders by metadata", the POST method endpoint and the request example use different URLs.

This discrepancy may confuse developers. The POST method's URL is correct, I think.

### Current content

The request example currently shows:

```
curl -i -X POST "https://api.box.com/2.0/files/12345" \
-H "authorization: Bearer " \
-H "content-type: application/json" \
-d '{
"from": "enterprise_123456.contractTemplate",
"query": "amount >= :value",
"query_params": {
"value": 100
},
"fields": [
"name",
"amount"
]
}'
```

### Expected content

The request example should use the correct endpoint:

```
curl -i -X POST "https://api.box.com/2.0/metadata_queries/execute_read" \
-H "authorization: Bearer " \
-H "content-type: application/json" \
-d '{
"from": "enterprise_123456.contractTemplate",
"query": "amount >= :value",
"query_params": {
"value": 100
},
"fields": [
"name",
"amount"
]
}'
```

### Link to the documentation page

https://developer.box.com/reference/post-metadata-queries-execute-read/