Feat(issues_grid_view): add issues grid view feature

What does this MR do and why?

Related issue: #323095 , #387022(MVC1)

Related JH issue: https://jihulab.com/gitlab-cn/gitlab/-/issues/2150

These MRs implements MVC1 described in this #387022. It revamps the issue page by adding a grid view (while keeping the list view) for both group and project issues. Users can customize the order of fields in the grid view and add or remove fields (with "id" and "title" being fixed fields), and their customization config is cached in the browser.

This is the first MR split from the original MR : !113012 (closed)

In this MR, we have introduced a feature flag (issues_grid_view), added relevant buttons to the tab, and included an empty grid view component, subsequent MR will add functions based on this MR.

This feature is controlled by the feature flag issues_grid_view.

MRs:

1. Current MR, Add feature flag, add tabs and add empty grid view div.
2. Implement the gridView function (We can see grid view now) : !121062 (closed) .
3. Add issue field drawer component, we can customize the grid header now.

/cc @JeremyWuuuuu @mtan-gitlab

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Open the feature flag issues_grid_view in rails console. (::Feature.enable(:issues_grid_view))
2. Go to the issue page of any group or project.
3. Observe.

MR acceptance checklist

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