Telegrafs - POST or PUT without request body leads to HTTP 500 internal server error

__Steps to reproduce:__
List the minimal actions needed to reproduce the behavior.

1. send a POST request to the `/telegrafs` endpoint or a PUT request to a `/telegrafs/{telegrafID}` endpoint but forget the request body data.

__Expected behavior:__
expected the fact that no request body data was sent to be detected and the issue handled gracefully with an HTTP 400 response and a message indicating the lack of data.

__Actual behavior:__
Server throws HTTP 500 internal server error.

__Environment info:__
testing against K8S_IDPE remocal

latest commit
```
commit b013fc31b31fabaf34e62b615ffaa0ebc088d3e2 (HEAD -> master, origin/master, origin/HEAD)
Author: influx-acs[bot] <107396960+influx-acs[bot]@users.noreply.github.com>
Date: Fri Nov 18 21:38:07 2022 +0000
```

Reproduce the missing-body POST request to `/telegrafs` and the missing-body PUT request to `/telegrafs/{telegrafID}` first. Locate the handlers for these endpoints and trace how an absent body is handled; done means both requests return HTTP 400 with a message indicating that request data is missing instead of HTTP 500.

Written by the indexing model from the issue text.