Refactor: Fix sonar lint CI

[Thykof]

Refactor the code to fix all issues reported by solar lint: https://sonarcloud.io/summary/new_code?id=massalabs_thyra-plugin-wallet&branch=main

Code smells: https://sonarcloud.io/project/issues?resolved=false&types=CODE_SMELL&sinceLeakPeriod=true&id=massalabs_thyra-plugin-wallet
starting with priority: blocker, critical, major, minor

[loonggamma]

@gregLibert @Thykof need priority on this as it's tech issue. Is it P3 for Mainnet?

[gregLibert]

@gregLibert @Thykof need priority on this as it's tech issue. Is it P3 for Mainnet?

We need to following code legacy oriented issues and start working on it after the ICO quest.

Futhermore this issue is huge and should split the different subject in multiple categories (meta issue)