Remove CONSTANT_KEYWORD from LiteralTests.java (#53606)

Author: astefan

x-pack/plugin/ql/src/test/java/org/elasticsearch/xpack/ql/expression/LiteralTests.java

@@ -20,7 +20,6 @@
 import java.util.function.Supplier;
 
 import static java.util.Collections.emptyList;
-import static org.elasticsearch.xpack.ql.type.DataTypes.CONSTANT_KEYWORD;
 import static org.elasticsearch.xpack.ql.type.DataTypes.BOOLEAN;
 import static org.elasticsearch.xpack.ql.type.DataTypes.BYTE;
 import static org.elasticsearch.xpack.ql.type.DataTypes.DOUBLE;
@@ -54,7 +53,7 @@ static class ValueAndCompatibleTypes {
             new ValueAndCompatibleTypes(ESTestCase::randomLong, LONG, FLOAT, DOUBLE, BOOLEAN),
             new ValueAndCompatibleTypes(ESTestCase::randomFloat, FLOAT, LONG, DOUBLE, BOOLEAN),
             new ValueAndCompatibleTypes(ESTestCase::randomDouble, DOUBLE, LONG, FLOAT, BOOLEAN),
-            new ValueAndCompatibleTypes(() -> randomAlphaOfLength(5), KEYWORD, CONSTANT_KEYWORD));
+            new ValueAndCompatibleTypes(() -> randomAlphaOfLength(5), KEYWORD));
 
     public static Literal randomLiteral() {
         ValueAndCompatibleTypes gen = randomFrom(GENERATORS);