add dependabot config

[tevo-nikita-ivashkov]

Why / What

This PR adds dependabot config

Reviewer Checklist (To be edited and marked by approver)

After approving the PR, the reviewer should check the boxes below. See the Reviewer Checklist company standard for more info on these bullet points.

• Do you understand the reasoning behind the need for the changes?
• Given only new or existing tests*, do you feel confident that all changes work as intended and solve the problem at hand?
• Are all success and failure paths accounted for in the tests? If not, are the omissions explained/justified?
• If coverage ignores are present, is justification provided inline (or linked to) or is a link to a ticket to address in the future provided?
• Are you willing to accept the same responsibility for this code as the author?

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• Overall: XX%

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[coneybeare]

love the new grouping