LogConfigurator resolveConfig  also reads .rpmnew or .bak files

Currently the LogConfigurator will attempt to read any file that starts with "logging." in the env.configFile() path.

A common practise is to suffix files with .bak or in case of package managers they often add a suffix if the file has been modified upstream.

Elasticsearch will read those values anyway and that might lead to very confusing logging behaviour.

I am not sure how to best approach this, either have a whitelist or a backlist of suffixes that are allowed/disallowed ?
I wonder about the added `toLowerCase`...I understand why you did it, but I'm not sure we should change this here. This way we would not only load less files (as we skip non allowed suffixes), but also more files at the same time (think of potentially any  LOGGING* or Logging* file that was ignored up until now). It's a minor thing but I would open another issue for discussion on making the filename case-insensitive and discuss it separately.