### Elasticsearch Version

8.8.0-SNAPSHOT

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

MacOS

### Problem Description

API when called is returning invalid response, on the same data terms aggs query runs fine 

![image](https://user-images.githubusercontent.com/3505601/220749805-ddf0d735-60d5-4e45-85bf-941ea3076a3f.png)


When run as aggs query 

![image](https://user-images.githubusercontent.com/3505601/220764360-49f7b648-8b15-43cf-afe2-01bd62e8ebc5.png)


### Steps to Reproduce

Queries are mentioned above ^^

### Logs (if relevant)

_No response_
x-pack/plugin/mapper-constant-keyword/src/main/java/org/elasticsearch/xpack/constantkeyword/mapper/ConstantKeywordFieldMapper.java
return new MatchAllDocsQuery();
            } else {
                return new MatchNoDocsQuery();
            }
        }
        @Override
        public Query regexpQuery(
            String regexp,
            int syntaxFlags,
            int matchFlags,
            int maxDeterminizedStates,
            MultiTermQuery.RewriteMethod method,
            SearchExecutionContext context
        ) {
            if (this.value == null) {
                return new MatchNoDocsQuery();
            }
            final Automaton automaton = new RegExp(regexp, syntaxFlags, matchFlags).toAutomaton(maxDeterminizedStates);
            final CharacterRunAutomaton runAutomaton = new CharacterRunAutomaton(automaton);
            if (runAutomaton.run(this.value)) {
                return new MatchAllDocsQuery();
            } else {
                return new MatchNoDocsQuery();
            }
        }
    }
    ConstantKeywordFieldMapper(String simpleName, MappedFieldType mappedFieldType) {
        super(simpleName, mappedFieldType, MultiFields.empty(), CopyTo.empty());
    }
    @Override