Initial gem files

[kostyanf14]

No description provided.

[github-advanced-security]

Rubocop found more than 10 potential problems in the proposed changes. Check the Files changed tab for more details.

[akihikodaki]

I don't think this is worth extracting into a distinct gem. This includes some hardcoded file names, and expects very specific assumptions like diffs are written in file, not generic IO. It is possible to convert it to more generic implementation, but only small portion of the code will remain after such conversion. Therefore, this gem is not likely to be useful outside of AutoHCK.

On the other hand, there is certainly some overhead of creating a gem. The number of the lines of the actual content in example, lib, and spec is 294, but the whole gem takes even 646 lines, which is more than twice. We will also need to update this gem in two steps: first in this repository, and later in AutoHCK to update gem version and make corresponding changes. We also need to duplicate our efforts to respond to dependabot, etc.

[kostyanf14]

@akihikodaki, We move this logic to a separate gem because we need it to run directly in Jenkins independently from AutoHCK.

Currently, we move it as is but we can extend the gem if found some new functionality for it.

[akihikodaki]

@kostyanf14 In that case we can simply add a new file which calls this logic to bin in AutoHCK repository. That will save the overhead I mentioned.