Jcastets/linter

[brmzkw]

The goal of this PR is not to fix the lint issues, but instead to add the linter to the CI to improve the quality of the future code.

We will probably need to spend some time to review what errors have been silenced and should have been handled instead.

[brmzkw]

To recap the discussion of this morning on Discord, I'll do the following:

1/ update this PR to regroup fixes in different commits. For example, there will be one commit for _ = flag.Parse, one commit for another type of error, and so on.
2/ I will remove the command find which is causing linting issues, and will not be included in the beta.
3/ The PR can then be merged to main.
4/ Then, I'll create an issue with the following content: "The commit silenced the linter. We need to review whether silencing was the right thing to do, if we should instead do something about it (eg. bubble up the error), or if we should update the linter configuration to ignore these errors and instead revert the commit". This issue will have to be reviewed to improve the current code.