Log input can misclassify renamed file as new file

Found via failing tests on main ([for example](https://buildkite.com/elastic/filebeat/builds/17764#0196f9cd-e97e-42d3-b15a-2ff8e39a9997)): there seems to be a race condition such that sometimes the log input detects that a file has been renamed, but can't update its metadata because its existing harvester hasn't finished, giving many log messages of the form `File rename detected but harvester not finished yet`. However, when the harvester does finish, the file is immediately reopened by a new harvester as a new file instead of finishing the metadata update.