Onboarding - set up your destination

[johnlafleur]

Once user set up their source in Onboarding, they should be invited to set up their destination:
https://www.figma.com/file/AODY4oi15iI5l0fbxHvobt/Daxtarity?node-id=5782%3A44298

in v1.0, we only support one destination. This might change in the future.

It should be the same behavior as for sources. But there should be 2 differences:

• user should be able to click on (1) create a source in the tabs of the header to go back to previous step (note that clicking on "(3) set up connection" shouldn't do anything until you reached that point)
• user should be able to click on "Source name" in the summary to go back to previous step as well

Summary of expected behavior (similar to source):
Setting up the name for the source and selecting a connector for the destination should be compulsory. So the button "Set up destination" should be disabled as long as all fields are not filled.

Once the user selected a connector, 2 things should happen:

• new fields should be displayed to set up the destination (defined by the API)
• a link towards our documentation for this connector should be displayed. Clicking on the link should display the docs page in a new tab.

@cgardens