Filebeat fails to harvest if a file and a symlink to that file is in the same directory

@treff7es1 I started to investigate this issue. The first thing I asked myself is what do we expect if there is a symlink to a file which is also in the same directory? Does it just add the orginal to our harvester list? Should we even "respect" symlinks or ignore them?

I couldn't reproduce the behaviour about not reading at all, but it currently reads the file twice (which is somehow expected as it treats the symlink like a file). Each symlink has its own inode ...