fix iceberg unit test

Author: Abacn

.github/trigger_files/beam_PostCommit_SQL.json

@@ -1,4 +1,4 @@
 {
   "comment": "Modify this file in a trivial way to cause this test suite to run ",
-  "modification": 3
+  "modification": 4
 }

sdks/java/io/iceberg/src/main/java/org/apache/beam/sdk/io/iceberg/FilterUtils.java

@@ -340,7 +340,7 @@ private static Object convertLiteral(SqlLiteral literal, String field, TypeID ty
         return literal.getValueAs(String.class);
       case DATE:
         LocalDate date;
-        if (SqlTypeName.STRING_TYPES.contains(typeName)) {
+        if (SqlTypeName.STRING_TYPES.contains(typeName) || SqlTypeName.UNKNOWN.equals(typeName)) {
           date = LocalDate.parse(literal.getValueAs(String.class));
         } else if (SqlTypeName.DATE.equals(typeName)) {
           DateString dateValue = literal.getValueAs(DateString.class);
@@ -351,7 +351,7 @@ private static Object convertLiteral(SqlLiteral literal, String field, TypeID ty
         return DateTimeUtil.daysFromDate(date);
       case TIME:
         LocalTime time;
-        if (SqlTypeName.STRING_TYPES.contains(typeName)) {
+        if (SqlTypeName.STRING_TYPES.contains(typeName) || SqlTypeName.UNKNOWN.equals(typeName)) {
           time = LocalTime.parse(literal.getValueAs(String.class));
         } else if (SqlTypeName.TIME.equals(typeName)) {
           TimeString timeString = literal.getValueAs(TimeString.class);
@@ -362,7 +362,7 @@ private static Object convertLiteral(SqlLiteral literal, String field, TypeID ty
         return DateTimeUtil.microsFromTime(time);
       case TIMESTAMP:
         LocalDateTime datetime;
-        if (SqlTypeName.STRING_TYPES.contains(typeName)) {
+        if (SqlTypeName.STRING_TYPES.contains(typeName) || SqlTypeName.UNKNOWN.equals(typeName)) {
           String value = literal.getValueAs(String.class);
           datetime = getLocalDateTime(value);
         } else if (SqlTypeName.DATE.equals(typeName)) {