PR introduced in #13819 was incorrect and was not
handling the situation where a buffer is full can
cause incessant amount of logs that would keep the
logger webhook overrun by the requests.
To avoid this only log failures to console logger
instead of all targets as it can cause self reference,
leading to an infinite loop.
Logger targets were not race protected against concurrent updates from for example `HTTPConsoleLoggerSys`.
Restrict direct access to targets and make slices immutable so a returned slice can be processed safely without locks.
This is to ensure that there are no projects
that try to import `minio/minio/pkg` into
their own repo. Any such common packages should
go to `https://github.com/minio/pkg`
