Mismatched decimal deserialization for spot price & twap between `osmosis-testing` and `cosmwasm`

[iboss-ptk]

As pointed out by @piobab, decimal deserialization for spot price & twap in osmosis-testing and cosmwasm are mismatched.

This commit demonstrate the problem piobab@3e10178

left: "0.944009649029192124"
right: "944009649029192124"

[iboss-ptk]

@piobab if you have some time slot, contribution would be very much appreciated, my time is now quite consumed by other focus area.

[piobab]

Sure, if I find some free slot I will contribute.