Docs should fetch device type information dynamically

[sradevski]

Currently we have a device-types.json file that is the source of truth for the getting started guide. This is quite error-prone and it needs to be manually updated, so we need to change it to fetch the device types info dynamically.

[sradevski]

Another place that will need updating see PR: #1443

[cywang117]

@vipulgupta2048 I believe this issue is already taken care of, see https://github.com/balena-io/docs/blob/master/templates/_devices.html where there is a dynamic query on page load which queries device types from balenaAPI.

Can I close this issue?

[cywang117]

@vipulgupta2048 Yeah this issue is definitely not solved -- it's referring to https://github.com/balena-io/docs/blame/master/config/dictionaries/device.json

[vipulgupta2048]

Yeap, we will remove this soon enough once Contracts can get provisioning instructions sorted.

[vipulgupta2048]

It finally did with the PR I merged here: balena-io/balena-sdk#1101
And, it's coming into effect with #2613