Repaired Fort Lonestar map

[Fixed](https://github.com/OpenRA/OpenRA/pull/7180/files#diff-058bf8510b263ff90d8d9483f8b34744R613) the instant win because of the short game option,
[added](https://github.com/OpenRA/OpenRA/pull/7180/files#diff-7a8e156d846a555ea42527ddb0fceac9R102) an "enemy units approaching" speech notification (hope that's okay),
updated fort-lonestar.lua
and added the map.yaml cleanup from #7164 .
This will stack `Enemy, Enemy Enemy units approaching` starting at wave 3 where multiple enemies are spawned almost next to each other, but I really like this. Much better than my debug text string dumped to the console. Maybe add a `bool notify` into the `Waves` array to check against and set it to false for all those short interval enemy reinforcements.