mtail locks watched files on Windows and prevents deletion

Heyo, new here.

Tested with 3.0.0-rc52
OS: Windows

Current environment produces log files with date/time strings in their file names, having to use glob expression with `-logs` .

Wanting to have:
* `poll_interval` 30s~
* `poll_log_interval` between 1-12 hrs

```
.\mtail.exe -logs "C:\somelogs\*\*.log" -progs "C:\mtail_programs\mtail" -poll_interval 30s -poll_log_interval 3h
```

Tested with `--expired_metrics_gc_interval `, `--stale_log_gc_interval`.

Is there a way for mtail to release files and directories?

Current Workaround
Having to create a scheduled task to create/remove symlinks to the desired date/time directories, which is then configured with `-logs`