Enhance file permission unit test

> Originally i opened that PR. But in the end they were arguing on thing i didn't see on our repo..

Yeah, I think the problem is caused by how the CI is building the application. The best approach is indeed to work on improving the test in order to make it OS agnostic by creating a file and setting some privilege to deny access. I created it some time ago and I did not consider the impact on other systems that can build the application.

I am opening a follow up issue to work on such improvement, in the while, we may even remove/comment the test in order to fix the problem described there.

_Originally posted by @squakez in https://github.com/apache/camel-k/issues/2561#issuecomment-896015636_

Start by locating the file-permission unit test referenced by the issue and reviewing the CI behavior described in issue 2561. Replace the environment-dependent setup with a test that creates a file and denies access through file permissions, then verify it works across the operating systems supported by the build; the issue names no test path or exact permission mechanism.

Written by the indexing model from the issue text.