I have ClickHouse server running in virtual environment that reports the following warning:

```
# clickhouse-client
ClickHouse client version 22.7.2.15 (official build).
Connecting to localhost:9000 as user default.
Connected to ClickHouse server version 22.7.2 revision 54457.

Warnings:
 * Linux is not using a fast TSC clock source. Performance can be degraded. Check /sys/devices/system/clocksource/clocksource0/current_clocksource

# cat /sys/devices/system/clocksource/clocksource0/current_clocksource
kvm-clock
```

It looks like a false positive as kvm-clock is considered a preferable clock source for kvm-based VMs.
https://opensource.com/article/17/6/timekeeping-linux-vms

Regardless of whether it's a bug or not, I'd like to have some mechanism that allows to disable particular warnings. There are may be other questionable warnings in the future.

{
    return getConfigRef().has("distributed_ddl");
}
void Context::setDDLWorker(std::unique_ptr<DDLWorker> ddl_worker)
{
    auto lock = getLock();
    if (shared->ddl_worker)
        throw Exception("DDL background thread has already been initialized", ErrorCodes::LOGICAL_ERROR);
    ddl_worker->startup();
    shared->ddl_worker = std::move(ddl_worker);
}
DDLWorker & Context::getDDLWorker() const
{
    auto lock = getLock();
    if (!shared->ddl_worker)
    {
        if (!hasZooKeeper())
            throw Exception("There is no Zookeeper configuration in server config", ErrorCodes::NO_ELEMENTS_IN_CONFIG);
        if (!hasDistributedDDL())
            throw Exception("There is no DistributedDDL configuration in server config", ErrorCodes::NO_ELEMENTS_IN_CONFIG);
        throw Exception("DDL background thread is not initialized", ErrorCodes::NO_ELEMENTS_IN_CONFIG);
    }
    return *shared->ddl_worker;
}
zkutil::ZooKeeperPtr Context::getZooKeeper() const