Fix game crash when a shadow buffer limit is exceeded

[xezon]

• Is complementary to Double shadow buffers in W3DBufferManager #604
• Fixes The game crashes when a certain 3D Shadow limit is exceeded TheSuperHackers/GeneralsGamePatch#53

This change fixes game crashes from exceeding the limits of MAX_VB_SIZES, MAX_IB_SIZES and MAX_NUMBER_SLOTS.

MAX_NUMBER_SLOTS is exceeded in the original game when more than 512 Scorpion tanks are rendered in the scene.

[codecov-commenter]

Codecov Report

Attention: 8 lines in your changes are missing coverage. Please review.

Comparison is base (cfa005f) 2.53% compared to head (6e21d1b) 2.53%.

Files	Patch %	Lines
...tform/w3dengine/client/shadow/w3dbuffermanager.cpp	0.00%	8 Missing ⚠️

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Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1101      +/-   ##
===========================================
- Coverage     2.53%    2.53%   -0.01%     
===========================================
  Files          949      949              
  Lines       110299   110307       +8     
  Branches     18881    18885       +4     
===========================================
  Hits          2800     2800              
- Misses      107095   107103       +8     
  Partials       404      404              

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