Add Dependabot to check actions

[abelsiqueira]

Description

Dependabot will check if the versions of the actions need to be updated. Like CompatHelper does, but dependabot is much more broad and well-known.

ref: https://docs.github.com/en/code-security/dependabot/working-with-dependabot/keeping-your-actions-up-to-date-with-dependabot

Related Issues

No response

[datejada]

Better after M1

[clizbe]

Sounds good to me.

[clizbe]

Covered by using BestieTemplate.jl.