The code of Method publishConfig of Class ConsulDynamicConfiguration:
```java
    @Override
    public boolean publishConfig(String key, String group, String content) throws UnsupportedOperationException {
        String normalizedKey = convertKey(group, key);
        return kvClient.putValue(normalizedKey + PATH_SEPARATOR + content);
    }
```
We want put a config with value with the "content", but the method just add the "content" to the key and put a null value.
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