Remove deadzone at the start of blastdoor open (#5648)

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## About The Pull Request

Removes a small bit of empty space at the start of the file so that it
plays immediately.

## Why It's Good For The Game

Right now there is a tiny delay between opening it and the sound playing
which is a bit jarring. This fixes that.

## Changelog

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:cl:
fix: Removed empty space at the start of the blast door opening sfx.
/:cl:

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