False positives on COM.FLOW.FileExistence error

### Expected behavior
we don't expect a COM.FLOW.FileExistence error :
- on "done" when using a loop with on a file (done < $file) (done is not a file in this case).
- on "$recipient" when using the command mail (recipient is not a file in this case).

### Actual behavior
With the following lines :
and

we get the this i-Code result :

### Steps to reproduce behavior

### Detection version
3.0