fix weight

[RustNinja]

Update weight for set price info extrinsic
more about issue:

Problem
The weight defined for the dispatchable function set_updated_coin_infos represents a computation longer than one second (1^12 units of weight = 1 second of computation).

Solution: specify weight limit for extrinsic that related to 1 read and 1 write and less than one sec.

[ebma]

I checked the benchmarking code and saw that the weight is so high because they feed 5000 coin_infos with one call. see here.

So instead of changing these weights manually as you did here, I would prefer if you instead change the benchmark to not feed 5000 but maybe like 30 or 50 values in one call. This should reduce the weight significantly and hopefully enough to resolve the other issue

[RustNinja]

ok