Stop CI testing on Dependabot branches pushed

[ybiquitous]

Which issue, if any, is this issue related to?

None.

Is there anything in the PR that needs further explanation?

Dependabot branches always come with pull requests, so I believe duplicate CI jobs on push and pull_request are useless. For example, see below:

[changeset-bot]

⚠️ No Changeset found

Latest commit: 3c6a5a1

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