* Proxmox inventory plugin - Fix string to dict conversion (#4348)
* Re-use the (defined but unused) `plaintext_configs` variable to list
configuration entries that should be ignored by the string to
dictionary conversion code. At this point, it only contains the
`description` string.
* Convert to a dictionary if the all substrings obtained by splitting
off the initial value with commas contain a `=` character
* Limit substring splitting to a single split, so that a substring
containing `a=b=c` will generate an `a` entry with value `b=c`.
* Added changelog fragment for PR #4349
* Fix changelog fragment for #4349
