Create abstractions for manipulation coinType format

[lumtis]

Describe the Issue

The cointype when emitting the event in Sui doesnt' include 0x prefix
We therefore use this no prefix format for the asset value in the zrc20 data to match directly with the data emitted from Sui.

However, there are different part of the code requiring to set the 0x prefix.

node/zetaclient/chains/sui/signer/signer_tx.go

Line 37 in 4ac8531

coinType = "0x" + cctx.InboundParams.Asset

(might be other in the future with whitelist tx)

This prefix is added manually, for better code clarity it might be better to create method abstracting this change, from the dev perspective, only a coinType type is used.

Alternative

Explore the possibility of emitting the type with 0x format on Sui and use this format everywhere in the code