Chain lightning CBM does electric damage instead of stab

[Dacendeth]

Summary

SUMMARY: Balance "Chainlightning CBM shot does electric damage now"

Purpose of change

The chainlightning CBMs shot does stab damage, which makes it able to wound shocker zombies with the initial projectile, this feels rather wrong as they're immune to electric shocks.

Describe the solution

Changed the fake item that the cbm uses from stab to electric damage.

Describe alternatives you've considered

Leaving it as it is.

Testing

Spawned a shocker zombie, a incandescent hulk, a shocker brute and shot them with the CBM and was unable to hurt any of them anymore.
Spawned a normal zombie and a kevlar hulk, damage to them was consistant and worked.

Additional context

[KorGgenT]

After inspecting the code with this change, it's still doing stab damage.
in player::fire_gun()

So to make this actually do electric damage, some more bughunting and C++ bugfixing is going to have to happen.

[anothersimulacrum]

Ugh, that's probably my fault. I'll look into that.

[Dacendeth]

Huh that's weird, wonder why changing it made it not hurt the shock zombies anymore when I tested it then.

[anothersimulacrum]

Works for me?

Thread 1 "cataclysm-tiles" hit Breakpoint 2, player::fire_gun (this=0x555559e4ddc0, target=..., shots=1, gun=...) at src/ranged.cpp:478
478	        auto shot = projectile_attack( make_gun_projectile( gun ), pos(), aim, dispersion, this, in_veh );
(gdb) n
479	        curshot++;
(gdb) p shot
$5 = {proj = {impact = {damage_units = std::vector of length 1, capacity 1 = {{type = DT_ELECTRIC, amount = 16, res_pen = 0, res_mult = 1, damage_multiplier = 0.875, unconditional_res_mult = 1, unconditional_damage_mult = 1}}}, speed = 1000, range = 10,
    critical_multiplier = 2, proj_effects = std::set with 3 elements = {[0] = "BOUNCE", [1] = "LIGHTNING", [2] = "WIDE"}, drop = std::unique_ptr<item> = {get() = 0x0}, custom_explosion = std::unique_ptr<explosion_data> = {get() = 0x55556b2a3150}}, hit_critter = 0x0,
  dealt_dam = {dealt_dams = {_M_elems = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}, bp_hit = bp_torso}, end_point = {x = 67, y = 69, z = 0}, missed_by = 1}