Fixes #4241

[ColombuxMaximus]

Fixes #4241 (Using a weapon model id for engineRequestModel and then replacing it crashes the game)

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• [x ] your code follows the coding guidelines
• [ x] your commit messages are informative ("update file.cpp" is unhelpful. "fix missing model in getVehicleNameFromModel" is helpful)

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create a draft pull request: https://github.blog/2019-02-14-introducing-draft-pull-requests/

Thank you!

[FileEX]

This is not a proper fix, just a workaround. It doesn't fix the crash, it only blocks the ability to use the weapon ID