Skip entry owners check for exclusion pattern

What does this MR do and why?

Problem

When the exclusion pattern(!) is used and entry owners are not defined, checks are still run on the exclusion owners.

Solution

When an exclusion pattern is defined, we should skip all checks on the entry owners

References

Related to #520956 (closed)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

• Enable codeowners_file_exclusions in console
• Create a new project and add a CODEOWNERS file with a line that has malformed user and an exclusion !*.js malformed @valid-user @valid-group another_malformed
• In the MR branch, it should not show any syntax errors. master will show a malformed error.