[vz-dev] [volkszaehler/vzlogger] 48b855: [api/influxdb] fix memory leak (fixup 6ab1bb7d)

[Thorben T.]

  Branch: refs/heads/master
  Home:   https://github.com/volkszaehler/vzlogger
  Commit: 48b855425857ce5aefe722dc00105c2fec4ec80c
      https://github.com/volkszaehler/vzlogger/commit/48b855425857ce5aefe722dc00105c2fec4ec80c
  Author: r00t <r00t at constancy.org>
  Date:   2022-02-17 (Thu, 17 Feb 2022)

  Changed paths:
    M include/api/InfluxDB.hpp
    M src/api/InfluxDB.cpp

  Log Message:
  -----------
  [api/influxdb] fix memory leak (fixup 6ab1bb7d)

also create header and header-list only once.
(previous code leaked one curl_slist struct per send() invocation)