The test class `KeywordFieldMapperTests` contains a switch statement with a branch that will never execute. The test uses a `between(x, y)` switch expression, but the `4` case is outside the randomised range. We need to fix this before #88739 can be merged. By "fix", I mean either remove the spurious case, or if we actually want it then extend the randomized range.
server/src/test/java/org/elasticsearch/index/mapper/KeywordFieldMapperTests.java
new String[] { "hello", "world" }
        );
        Analyzer q = ft.getTextSearchInfo().searchQuoteAnalyzer();
        assertTokenStreamContents(q.tokenStream("", "Hello World"), new String[] { "hello world" });
        mapperService = createMapperService(mapping(b -> {
            b.startObject("field").field("type", "keyword").field("split_queries_on_whitespace", true).endObject();
            b.startObject("field_with_normalizer");
            {
                b.field("type", "keyword");
                b.field("normalizer", "lowercase");
                b.field("split_queries_on_whitespace", false);
            }
            b.endObject();
        }));
        fieldType = mapperService.fieldType("field");
        assertThat(fieldType, instanceOf(KeywordFieldMapper.KeywordFieldType.class));
        ft = (KeywordFieldMapper.KeywordFieldType) fieldType;
        assertTokenStreamContents(
            ft.getTextSearchInfo().searchAnalyzer().analyzer().tokenStream("", "Hello World"),
            new String[] { "Hello", "World" }
        );
        fieldType = mapperService.fieldType("field_with_normalizer");
        assertThat(fieldType, instanceOf(KeywordFieldMapper.KeywordFieldType.class));
        ft = (KeywordFieldMapper.KeywordFieldType) fieldType;
        assertThat(ft.getTextSearchInfo().searchAnalyzer().name(), equalTo("lowercase"));
        assertTokenStreamContents(
            ft.getTextSearchInfo().searchAnalyzer().analyzer().tokenStream("", "Hello World"),
            new String[] { "hello world" }
        );
    }