Got a 204 response when writing data using HTTP/1.0, but no data is showing

__Steps to reproduce:__

`Send HTTP/1.0 POST-request with line protocol in request body to the /write endpoint`

```
curl --request POST "http://localhost:8086/api/v2/write?org=YOUR_ORG&bucket=YOUR_BUCKET&precision=s" \
--header "Authorization: Token YOURAUTHTOKEN" \
--header "Content-Encoding: application/gzip" \
--data-raw "mem,host=host1 used_percent=23.43234543 1617612198" # timestamp of now

# got: HTTP/1.1 204 No Content
```

then query:

```
curl -i --request POST \
http://localhost:8086/api/v2/query?org=YOUR_ORG \
--header 'Authorization: Token YOURAUTHTOKEN' \
--header 'Accept: application/csv' \
--header 'Content-type: application/vnd.flux' \
--data 'from(bucket:"YOUR_BUCKET")
|> range(start: -100h)
|> filter(fn: (r) => r._measurement == "mem")
|> aggregateWindow(every: 1h, fn: mean)'

# got: HTTP/1.1 200 OK
```

But NOTHING will not print!
I first got this issue in the python API.
Sometime a measurement data will inject successfully, but sometimes not. (with same code!)
I tested this process with other ways(like above) and got the same result.

__Expected behavior:__
print result of query!

__Actual behavior:__
Nothing will be printed in the result for the quer

__Environment info:__

* System info: Linux 5.4.0-70-generic x86_64
* InfluxDB version: InfluxDB 2.0.4 (git: 4e7a59bb9a) build_date: 2021-02-08T17:47:02Z

Start by reproducing the HTTP/1.0 POST to the /write endpoint with the supplied curl command, then query the same bucket through /api/v2/query. Compare cases where the response is 204 but the measurement is absent, including the Python API path; done means successfully written data is returned by the query.

Written by the indexing model from the issue text.