Add OR filtering for author on group/project issues list

What does this MR do and why?

This MR adds OR filtering for author on the group/project issues list.

No changelog required as it's behind the feature flag or_issuable_queries, defaulted off.

Issue: #23532 (closed)

Screenshots or screen recordings

Screen_Recording_2022-11-11_at_11.21.29_am

How to set up and validate locally

1. In rails console enable the feature flag

   Feature.enable(:or_issuable_queries)

2. Visit any group or project issues list pages such as http://127.0.0.1:3000/h5bp/html5-boilerplate/-/issues/
3. Test OR filtering in the filtered search bar

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.