bug fix

flak41 and mk103a1

优化了火箭炮的相关内容；
取消了坦克歼击车移动开火机制，同时提高了坦克歼击车和反坦克炮以及重型防空炮在射击目标前有更长的瞄准时间(减少它们出现“甩狙”的情况)；
修正了苏联几款重坦的坦克炮的装填时间；
细化了一次性火箭筒和火箭筒：可装填式火箭筒的破甲弹添加了爆炸效果，同时允许ai(包括玩家单位)在没有敌人坦克的情况下对掩体里或者平地上的敌人步兵单位发射破甲弹(一次性火箭筒则只能被ai用来打击载具).

Optimized the rocket artillery-related content;
Removed the firing-while-moving mechanic for tank destroyers and increased the aiming time for tank destroyers, anti-tank guns, and heavy anti-aircraft guns before firing (to reduce "flick-shot" scenarios);
Fixed the reload time of tank guns for several Soviet heavy tanks;
Further distinguished disposable rocket launchers from reloadable ones: Added explosive effects to the HEAT rounds of reloadable rocket launchers, and allowed AI (including player units) to fire HEAT rounds at enemy infantry in cover or on open ground when no enemy vehicles are present (disposable rocket launchers can only be used by AI to engage vehicles).