Adding datasource picker and datalinks

[srclosson]

The datasource picker and datalinks are used in Splunk, but decoupled so the control can be reusable

[ryantxu]

still super nervous about this repo 😬

Lets make sure it has a plan for how to stay in sync with core

[kminehart]

@ryantxu Don't be nervous! :D

[srclosson]

We should actually come up with a plan for this. Perhaps even print the plan in the README?

I can talk to Luke and see if it's possible to set something up.

[vickyyyyyyy]

still super nervous about this repo 😬

Lets make sure it has a plan for how to stay in sync with core

We spoke to Alex and Luke and they suggested we have a regular (weekly or bi-weekly) sync space to gather all FE Enterprise and OSS things so everyone is aware of what's going on 😄 This way we can also discuss if any components we come up with can also be helpful in the core library.

For more context, they agreed that while we do have Enterprise-specific UIs, it would be great to incorporate all the work into the design system and also a single UI library.

[vickyyyyyyy]

LGTM! Good to see many tests being added! 🔥 🔥 🔥

Just left a few comments and nit suggestions 😄

I noticed the expect assertions are inside of the act wrapper - the act API is for wrapping interactions with your applications, like event firing, so the expect assertions are normally left outside and not included within the wrapper.

I think the awaits within the act wrappers can also be removed and another nit: the onChange handlers can be passed in jest.fn() rather than () => {} if we don't care about them

EDIT: Forgot to ask, can we add some stories for the new components so we have examples of their usages? 🙏

[vickyyyyyyy]

Suggested change

	// import { Button } from '@grafana/ui';
	// import { DataLink } from './DataLink';
	// import { act } from 'react-dom/test-utils';
	// import { Button } from '@grafana/ui';
	// import { DataLink } from './DataLink';
	// import { act } from 'react-dom/test-utils';