Intent to implement: automate dependency updates

### Is your feature request related to a problem? Please describe.

Some time ago GitHub acquired Dependabot, which allows to automate dependency update process, to make sure that the package works with latest versions of its dependencies and that all security vulnerabilities are addressed. We could consider enabling it for this repository.

### Describe the solution you'd like

I'd love to add a configuration for Dependabot to this repository, so we can benefit from it.

### Describe alternatives you've considered

There are more tools for dependency updates, but Dependabot is the most "official" one since the acquisition.

### Additional context