use `ukey` package from `sdk-utils`

[mtsitrin]

          nice util!, but it's not general purpose

can you add it to https://github.com/dymensionxyz/sdk-utils under a new package ukey and make it more generic by removing mention of 'queue' and 'end'

Originally posted by @danwt in https://github.com/dymensionxyz/dymension/pull/1006#discussion_r1689523792