Pipeline badge should show the parent commits status if the current status is skipped and ignore_skipped is true

What does this MR do?

Currently the ignore_skipped feature is not working as expected. See issue #326513 (closed)

The current behavior is that if the latest pipeline status for the current commit is skipped the latest non-skipped status for the current commit will be returned, otherwise unknown.

This MR will change that behavior to look for the latest pipeline status of the parents commit status instead of directly returning unknown. If no parent is available or the current commit was a merge commit it will also return unknown.

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have included a changelog entry.
  • I have not included a changelog entry because _____.
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Related to #326513 (closed)