Exclude specific issues during shellcheck scan (closes #22)

[asadmansr]

Pull Request Checklist

• [x] I have created an issue prior to creating this pull request
• [x] I have provided a detailed description and motivation regarding the change below
• [x] I have updated the test suite and documentation to support my change

Corresponding Issue

Issue already attached.

Description of Change

This features allows the shell-linter github action to exclude specific issues when running the ShellCheck linter. This is useful for accepting lint issues that are not required to be fixed at the moment or at all depending on the requirement.

Motivation and Context

Enhances the feature set of Shell-Linter and also a feature request by an user.

Testing Steps

Added test cases to support the development

Risks

N/A

Additional Information

Updated the README on how users can apply these changes to their projects.