As a DS designer and developer, I want to have a new popover component available, because it is needed in the Simple Query Builder.
**ACs**
[] The popover component is implemented according to the [[ https://www.figma.com/file/gi3JYwSUQYhKS0mHwK25cQwi/WiKit?node-id=4270%3A124 | Figma specs ]] and follows the behavior and accessibility principles defined in the [[ https://docs.google.com/presentation/d/1GB9WcQDQDYaf_kr0RvuaAuadKLPRytdcZ1vL78N2vx0/edit#slide=id.gb58b70b70c_1_1 | component documentation ]].
[] The popover's component-level tokens ([[ https://github.com/wmde/wikit/pull/366 | available in this PR ]]) are created according to the naming convention used to style the component and provide all the needed styling values
[] The popover is documented in Storybook according to the specifications (see below)
**Position**
Popovers do not have states, but we need to make it possible for implementers to define their position in relation to the element that triggers them (see notes):
[] Top: right, center, left
[] Bottom: right, center, left
[] Left: bottom, center, top
[] Right: bottom, center, top
**Storybook:**
This component has its own pages in Storybook, included by alphabetical order ([[ https://docs.google.com/document/d/1loENZ13z5s_Nes4exm5Z9d5S3PnR7F_0brv5azQ5XB4/edit | see structure ]]):
[] A //Popover// page including controls: they allow users to enter custom text to replace the default content and to change the popover position
**Notes:**
* It would be ideal if the position of the popover could be defined via prop
* A very similar (but slightly more complex) version of this component was implemented by the Tainted References team ([[ https://doc.wikimedia.org/Wikibase/master/js/tainted-ref-storybook/?path=/story/popper--popper-component | see component in Storybook ]])