Bank Machines now accept coins (#90494)

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## About The Pull Request
This is my first attempt at actually manipulating BYOND code, so I'm
using this pull request as a test. ~~I'm pushing a branch of my own
repository, so I should be able to test and make sure that I got
everything right.~~
NEVERMIND THIS WAS PUSHING INTO MASTER but it's fine, because I wrote it
as a rough draft and it should still make do. I'll just edit it to fix
it.

I submit a bug report a week ago for something that I found, and it's
basically slipped under the radar. At the same time, it was only three
lines to make this fix, so it seemed like a very easy attempt to make do
with.
Despite having monetary value, coins were not considered a valid vector
for cashing in at bank machines, only cash and holochips. This didn't
really make sense to me, so I decided it should be fixed. Since it was a
bug report that I submit, it doesn't feel right to use the Fix tag, so
I'm guessing QoL is more appropriate?
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## Why It's Good For The Game
Most coins have monetary value, so there's no real reason they can't be
accepted like cash or holochips. Valueless coins still attack the
machine, but if they have some value to them, then they'll be cashed in.
Closes https://github.com/tgstation/tgstation/issues/90381.
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🆑
qol: Bank machines accept coins of monetary value
/🆑

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---------

Co-authored-by: safey <safey@ncsu.edu>

code/game/machinery/bank_machine.dm

@@ -51,6 +51,9 @@
 	else if(istype(weapon, /obj/item/holochip))
 		var/obj/item/holochip/inserted_holochip = weapon
 		value = inserted_holochip.credits
+	else if(istype(weapon, /obj/item/coin))
+		var/obj/item/coin/inserted_coin = weapon
+		value = inserted_coin.value
 	if(value)
 		if(synced_bank_account)
 			synced_bank_account.adjust_money(value)