Unified resources view improvements

[gzdunek]

This PR addresses some minor issues in the UnifiedResources that were found during the work on integrated search bar in Connect.
I also changed the loading cards styling a bit (this was feedback from Kenny)
Before:

After:

While I was on it, I refactored it slightly. There is no need in setting up setTimeout 24 times if we can do this once.

[gzdunek]

We wanted to decrease this, I'll confirm it with Kenny.

[gzdunek]

Actually, I will just change it.

[avatus]

@rudream added another loading skeleton component for list view and realized that the colors in light mode were off. Can we take his updates to the colors and add them here?

[rudream]

LGTM. I applied these changes to the new skeleton loader for list items which I added in this PR: #34381

[gzdunek]

@rudream added https://github.com/gravitational/teleport/pull/34381for list view and realized that the colors in light mode were off. Can we take his updates to the colors and add them here?

I think we can keep them in his PR, we use the same Shimmer component so after we merge that PR everything will use the updated colors.

[gzdunek]

I refactored the loading skeleton a bit, now it expects an Element prop where we can pass LoadingCard and LoadingListItem. The LoadingSkeletion is now only responsible for the timeout and for rendering the passed Element.

[public-teleport-github-review-bot]

@gzdunek See the table below for backport results.

Branch	Result
branch/v14	Create PR