Detect new ecosystems

[vidwah-nte]

Is your feature request related to a problem?

If you have a dependabot.yml with config for e.g. ecosystem maven, then add a new ecosystem in the same project (i.e. npm), then evergreen won't try to update dependabot.yml to include npm.

Describe the solution you'd like

A new PR/Issue should be created when a project contains a dependabot.yml-file, but with missing ecosystems.

Describe alternatives you've considered

No response

Additional context

No response