Clarification on image `BuildConfig` files

[michael-valdron]

Which area this feature is related to?

/area documentation

Which area is this documentation change is related to?

/area api

Issue details

What mistake did you find / what is missing in the documentation?

Currently, the documentation does not provide clarification for new users how a BuildConfig file for building container images differs from a devfile, only provides limited instruction on how a devfile uses a BuildConfig file such as with a Dockerfile in 'Adding an image component', and does not provide what BuildConfig devfiles support (currently only dockerfiles).

Here is what is needed to clarify:

1. What a devfile is that a BuildConfig is not and vice versa
2. Brief showcase of how a BuildConfig can be references in a devfile using the kubernetes component
3. Brief showcase of how to migrate from BuildConfig and move all information within the devfile
4. What BuildConfig file(s) are supported by devfiles (e.g. what elements in BuildConfig are supported).

[michael-valdron]

Due to the backlog of items in this past sprint, this issue will be targeted for the upcoming sprint.

[github-actions]

This issue is stale because it has been open for 90 days with no activity. Remove stale label or comment or this will be closed in 60 days.

[michael-valdron]

This is a future addition that is planned to occur and part of a ongoing epic, removing the stale status.

[maysunfaisal]

We decided to move it as a devtools week item