Links in getting started guide should open in new tab

[alisondavis17]

Currently, links in the getting started guide open in the same tab, but links should open in new tabs so the user can keep the getting started guide open.

Examples of links that open in same tab but should open in a new tab:

[zwalchuk]

@craig-mulligan not sure where to fix this, I'm happy to fix if you show me where

[craigmulligan]

@zwalchuk, so we can either add the links as html for example <a href="url" target="_blank">my link</a> or we could add some special markdown syntax for custom attributes.

I'd vote for the custom syntax as it'll keep things readable. To do that we need to expose the markdown renderer from the underlying doxx library, which should be possible right @emirotin?

[poshrolls]

Topic for ProductOS / BalenaOS call - bigger issue for all docs.

[vipulgupta2048]

Closing this in favor of #2621