fix(tooltip): Remove x pad for topright positions

What does this MR do?

This MR fixes the topright positioning offset by removing some x padding that is inconsistent with Bootstrap's styles.

It also adds some storyshots for topright and topleft positioning of tooltip.

Before	After

Also see Bootstrap's tooltip style:

Integration screenshots

gitlab!35184 (comment 367009367)

Note that if offset is set, it looks like top and topright are treated the same which is a good thing 😄

Tooltip with topright and offset	Tooltip with top and offset	Tooltip with topright no offset

Does this MR meet the acceptance criteria?

Conformity

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• GitLab UI's contributing guidlines.
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  • GitLab: mr_url
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• Added the ~"component:*" label(s) if applicable.