Fix English pilot_f_ill_m01a.utf audio entries

[BC46]

The UTF file pilot_f_ill_m01a contains higher pitched versions of audio entries from pilot_f_ill_m01. We've included the unused pitch variations in faction_prop.ini so you don't hear the same exact voices in space every time. I had a listen to all the pitch variations, and they all sound fine, except for pilot_f_ill_m01a unfortunately. For some reason, the voices sound very squeaky and obnoxious, almost as if some alien robot filter has been applied; not very nice to listen to. I checked the German version of the same UTF file and that one seems completely fine. Therefore, I think we should have a go at fixing the English version ourselves.

The idea I have is to take all the entries from pilot_f_ill_m01.utf, increase the pitch slightly (kind of like all the other higher pitch variations), and insert them in into pilot_f_ill_m01a.utf. Unfortunately I couldn't find a way to properly automate the pitch increase without modifying the audio length. Since it'd be extremely tedious to modify and re-render 642 different audio files manually, I'll just add this to the backlog for now.

While we're at it, we might as well create pilot_f_leg_m01a (higher pitch version of pilot_f_leg_m01), since that one doesn't exist while it should. Probably has to be done in German, French and Russian too.