Looks like https://github.com/ClickHouse/ClickHouse/pull/21303 is broke also "clear column" for such columns.

How to reproduce:

```
CREATE TABLE test.TTAdmLog
(
    `ts` DateTime,
    `event_date` Date DEFAULT toDate(ts),
    `impression_id` String DEFAULT '',
    `creative_id` String DEFAULT '',
    `creative_adm` String DEFAULT '',
    `impression_id_compressed` FixedString(16) DEFAULT UUIDStringToNum(impression_id),
    `impression_id_hashed` UInt16 DEFAULT reinterpretAsUInt16(impression_id_compressed),
)
ENGINE = ReplicatedMergeTree('/clickhouse/tables/{shard}/TTAdmLogTest', '{replica}')
PARTITION BY toMonday(event_date)
ORDER BY (event_date, impression_id_hashed)
SAMPLE BY impression_id_hashed
SETTINGS replicated_deduplication_window = 1000, replicated_deduplication_window_seconds = 864000, index_granularity = 8192

CREATE MATERIALIZED VIEW test.TTView
(
    `event_date` Date,
    `creative_id` String,
    `creative_adm` AggregateFunction(anyLast, String),
)
ENGINE = ReplicatedAggregatingMergeTree('/clickhouse/tables/{shard}/TTViewTest', '{replica}', event_date, (event_date, creative_id), 8192) AS
SELECT 
    toStartOfMonth(event_date) AS event_date,
    arrayJoin(splitByChar(',', creative_id)) AS creative_id,
    anyLastState(creative_adm) AS creative_adm,
FROM test.TTAdmLog
GROUP BY 
    event_date,
    creative_id,

```


ClickHouse server version 20.9.3 revision 54439.

```
alter table test.TTAdmLog clear column creative_adm in partition '2021-03-22'

OK

```
ClickHouse server version 21.4.3 revision 54447.

```
alter table test.TTAdmLog  clear column creative_adm in partition '2021-03-22'

DB::Exception: Trying to ALTER DROP column creative_adm which is referenced by materialized view ['TTView'].

```

{
    
    if (!new_type->canBeUsedAsVersion())
        throw Exception("Cannot alter version column " + backQuoteIfNeed(column_name) +
            " to type " + new_type->getName() +
            " because version column must be of an integer type or of type Date or DateTime"
            , ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN);
    auto which_new_type = WhichDataType(new_type);
    auto which_old_type = WhichDataType(old_type);
    
    if ((which_old_type.isInt() && !which_new_type.isInt())
        || (which_old_type.isUInt() && !which_new_type.isUInt())
        || (which_old_type.isDate() && !which_new_type.isDate())
        || (which_old_type.isDateTime() && !which_new_type.isDateTime())
        || (which_old_type.isFloat() && !which_new_type.isFloat()))
    {
        throw Exception("Cannot alter version column " + backQuoteIfNeed(column_name) +
            " from type " + old_type->getName() +
            " to type " + new_type->getName() + " because new type will change sort order of version column." +
            " The only possible conversion is expansion of the number of bytes of the current type."
            , ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN);
    }
    
    if (new_type->getSizeOfValueInMemory() < old_type->getSizeOfValueInMemory())
    {
        throw Exception("Cannot alter version column " + backQuoteIfNeed(column_name) +
            " from type " + old_type->getName() +
            " to type " + new_type->getName() + " because new type is smaller than current in the number of bytes." +
            " The only possible conversion is expansion of the number of bytes of the current type."
            , ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN);