…rs (#8180)

# About the pull request

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As the title says.

Closes #8179

# Explain why it's good for the game
Modifying gun damage this way is really buggy and led to a bug (#8179)
that lets people stack a damage multiplier infinitely.

A more comprehensive solution would be to, instead, have a gun instance
stored in this attachment so that it handles all its own variables,
damage multiplers, et cetera, instead of trying to modify the original
weapon. This would require an overhaul and is not something I'm opposed
to someone doing, but this simple solution should suffice for fixing the
exploit.

# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

Put screenshots and videos here with an empty line between the
screenshots and the `<details>` tags.

</details>


# Changelog
:cl:
fix: Fixed an exploit that lets you increase your weapon's damage
multiplier infinitely.
/:cl: