Update examples to use ecosystem specific images

[yeikel]

Now that the dependabot/dependabot-core docker image is no longer updated as we are building ecosystem-specific images the examples need to be updated to reflect that

[jeffwidman]

Yep, we know we need to do something here, but there's some design decisions so we aren't quite clear on the path forward yet.

In the meantime I put this up to provide a heads up:

• https://github.com/dependabot/dependabot-script/pull/906

[sheim-dev]

Is there any progress on this yet?

If there's any documentation or at least some hints available on how to switch to the ecosystem-specific images, I would be willing to help out with adapting the dependabot-script repo to those.