(you don't have to strictly follow this form)

It seems that CH doesn't support  `FORMAT CustomSeparated` with http request
https://github.com/ClickHouse/ClickHouse/issues/12744#issuecomment-663738562

When I make a request with `format_custom_field_delimiter='^'`, I got an error
```
Code: 49, e.displayText() = DB::Exception: There is no checkpoint (version 20.1.2.4 (official build)) 
```
Bash script:
```
#!/bin/bash

find . -type f -name 'j.log' | while read f; do
  curl "http://localhost:8123
/?query=INSERT%20INTO%20mydb%20FORMAT%20CustomSeparated%20SETTINGS%20format_custom_escaping_rule%3D%27CSV%27%2C%20format_custom_field_delimiter%20%3D%20%27%5E%27" --data-binary "@${f}"
done
```
But all is OK, when I do it with client:
```
cat j.log |clickhouse-client  -q "INSERT into mydb FORMAT CustomSeparated SETTINGS format_custom_escaping_rule='CSV', format_custom_field_delimiter = '^'"
```


**How to reproduce**
* Which ClickHouse server version to use
 version 20.13.1.1 and github build `commit 6e34a0b71efc0e5af1cfb05b77a5e7b2568a2e49`
* Which interface to use, if matters
* Non-default settings, if any
* `CREATE TABLE` statements for all tables involved
```
CREATE TABLE mydb
(
	datetime  String,
	d1 String,
	d2 String
)
engine=MergeTree()
ORDER BY d1
SETTINGS index_granularity = 8192;
```
* Sample data for all these tables, use [clickhouse-obfuscator](https://github.com/ClickHouse/ClickHouse/blob/master/programs/obfuscator/Obfuscator.cpp#L42-L80) if necessary

j.log:
```
2021-Jan^d1^d2
```

* Queries to run that lead to unexpected result

**Expected behavior**
A clear and concise description of what you expected to happen.

**Error message and/or stacktrace**
If applicable, add screenshots to help explain your problem.

**Additional context**
Add any other context about the problem here.

if (input_function)
                {
                    StoragePtr storage = context.executeTableFunction(input_function);
                    auto & input_storage = dynamic_cast<StorageInput &>(*storage);
                    auto input_metadata_snapshot = input_storage.getInMemoryMetadataPtr();
                    BlockInputStreamPtr input_stream = std::make_shared<InputStreamFromASTInsertQuery>(
                        ast, istr, input_metadata_snapshot->getSampleBlock(), context, input_function);
                    input_storage.setInputStream(input_stream);
                }
            }
        }
        else
            
            context.resetInputCallbacks();
        auto interpreter = InterpreterFactory::get(ast, context, SelectQueryOptions(stage).setInternal(internal));
        std::shared_ptr<const EnabledQuota> quota;
        if (!interpreter->ignoreQuota())
        {
            quota = context.getQuota();
            if (quota)
            {
                quota->used(Quota::QUERIES, 1);
                quota->checkExceeded(Quota::ERRORS);
            }
        }
        StreamLocalLimits limits;
        if (!interpreter->ignoreLimits())
        {
            limits.mode = LimitsMode::LIMITS_CURRENT;
            limits.size_limits = SizeLimits(settings.max_result_rows, settings.max_result_bytes, settings.result_overflow_mode);